<PAGE>
                                  EXHIBIT 10.1

CONTACT:  CUSTOMER SERVICES -- CTSLINK
          WELLS FARGO BANK MINNESOTA, N.A.
          SECURITIES ADMINISTRATION SERVICES
          7485 NEW HORIZON WAY
          FREDERICK, MD  21703
          WWW.CTSLINK.COM
          TELEPHONE:         (301) 815-6600
          FAX:               (301) 315-6660

                               SMT SERIES 2002-12
                           RECORD DATE: JULY 31, 2003
                       DISTRIBUTION DATE: AUGUST 20, 2003

                     CERTIFICATEHOLDER DISTRIBUTION SUMMARY

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------------
                                   Certificate      Certificate
                                      Class         Pass-Through          Beginning             Interest           Principal
 Class             CUSIP           Description          Rate         Certificate Balance      Distribution        Distribution
------------------------------------------------------------------------------------------------------------------------------
<S>              <C>               <C>              <C>              <C>                      <C>                <C>
   A             81744BAA4             SEN              1.55000%        1,024,267,562.43      1,323,012.26       17,103,687.16
  X-1            81744BAB2             IO               1.06627%                    0.00        215,158.13                0.00
  X-2            81744BAC0             IO               1.16490%                    0.00        775,751.67                0.00
  A-R            81744BAD8             SEN              3.16651%                    0.00              0.00                0.00
  B-1            81744BAE6             SUB              1.95000%           16,815,000.00         27,324.37                0.00
  B-2            81744BAF3             SUB              2.69842%            8,968,000.00         20,166.20                0.00
  B-3            81744BAG1             SUB              2.69842%            6,165,000.00         13,863.14                0.00
  B-4            SMT0212B4             SUB              2.69842%            2,802,000.00          6,300.81                0.00
  B-5            SMT0212B5             SUB              2.69842%            1,681,000.00          3,780.04                0.00
  B-6            SMT0212B6             SUB              2.69842%            4,486,095.46         10,087.81                0.00
------------------------------------------------------------------------------------------------------------------------------
Totals                                                                  1,065,184,657.89      2,395,264.43       17,103,687.16
------------------------------------------------------------------------------------------------------------------------------
</TABLE>

<TABLE>
<CAPTION>
--------------------------------------------------------------------------------------------
                   Current         Ending Certificate          Total            Cumulative
 Class          Realized Loss           Balance             Distribution       Realized Loss
--------------------------------------------------------------------------------------------
<S>             <C>                <C>                     <C>                 <C>
   A                     0.00        1,007,163,875.27      18,426,699.42                0.00
  X-1                    0.00                    0.00         215,158.13                0.00
  X-2                    0.00                    0.00         775,571.67                0.00
  A-R                    0.00                    0.00               0.00                0.00
  B-1                    0.00           16,815,000.00          27,324.37                0.00
  B-2                    0.00            8,968,000.00          20,166.20                0.00
  B-3                    0.00            6,165,000.00          13,863.14                0.00
  B-4                    0.00            2,802,000.00           6,300.81                0.00
  B-5                    0.00            1,681,000.00           3,780.04                0.00
  B-6                    0.00            4,486,095.46          10,087.81                0.00
--------------------------------------------------------------------------------------------
Totals                   0.00        1,048,080,970.73      19,498,951.59                0.00
--------------------------------------------------------------------------------------------
</TABLE>

All distributions required by the Pooling and Servicing Agreement have been
calculated by the Certificate Administrator on behalf of the Trustee.
<PAGE>
                        PRINCIPAL DISTRIBUTION STATEMENT

<TABLE>
<CAPTION>
----------------------------------------------------------------------------------------------------------------------------
                                           Beginning           Scheduled       Unscheduled
                   Original Face          Certificate          Principal        Principal                           Realized
   Class               Amount               Balance          Distribution      Distribution       Accretion         Loss (1)
----------------------------------------------------------------------------------------------------------------------------
<S>               <C>                   <C>                  <C>               <C>                <C>               <C>
     A            1,080,076,000.00      1,024,267,562.43             0.00      17,103,687.16           0.00             0.00
    X-1                       0.00                  0.00             0.00               0.00           0.00             0.00
    X-2                       0.00                  0.00             0.00               0.00           0.00             0.00
    A-R                     100.00                  0.00             0.00               0.00           0.00             0.00
    B-1              16,815,000.00         16,815,000.00             0.00               0.00           0.00             0.00
    B-2               8,968,000.00          8,968,000.00             0.00               0.00           0.00             0.00
    B-3               6,165,000.00          6,165,000.00             0.00               0.00           0.00             0.00
    B-4               2,802,000.00          2,802,000.00             0.00               0.00           0.00             0.00
    B-5               1,681,000.00          1,681,000.00             0.00               0.00           0.00             0.00
    B-6               4,486,095.46          4,486,095.46             0.00               0.00           0.00             0.00
----------------------------------------------------------------------------------------------------------------------------
Totals            1,120,993,195.46      1,065,184,657.89             0.00      17,103,687.16           0.00             0.00
----------------------------------------------------------------------------------------------------------------------------
</TABLE>

<TABLE>
<CAPTION>
----------------------------------------------------------------------------------------------------
                 Total Principal     Ending Certificate    Ending Certificate        Total Principal
   Class            Reduction             Balance              Percentage             Distribution
----------------------------------------------------------------------------------------------------
<S>              <C>                 <C>                   <C>                       <C>
     A             17,103,687.16      1,007,163,875.27             0.93249352          17,103,687.16
    X-1                     0.00                  0.00             0.00000000                   0.00
    X-2                     0.00                  0.00             0.00000000                   0.00
    A-R                     0.00                  0.00             0.00000000                   0.00
    B-1                     0.00         16,815,000.00             1.00000000                   0.00
    B-2                     0.00          8,968,000.00             1.00000000                   0.00
    B-3                     0.00          6,165,000.00             1.00000000                   0.00
    B-4                     0.00          2,802,000.00             1.00000000                   0.00
    B-5                     0.00          1,681,000.00             1.00000000                   0.00
    B-6                     0.00          4,486,095.46             1.00000000                   0.00
----------------------------------------------------------------------------------------------------
Totals             17,103,687.16      1,048,080,970.73             0.93495748          17,103,687.16
----------------------------------------------------------------------------------------------------
</TABLE>

(1) Amount does not include excess special hazard, bankruptcy, or fraud losses
unless otherwise disclosed. Please refer to the prospectus supplement for a full
description.

                    PRINCIPAL DISTRIBUTION FACTORS STATEMENT

<TABLE>
<CAPTION>
--------------------------------------------------------------------------------------------------------------------------
                                      Beginning           Scheduled        Unscheduled
              Original Face          Certificate          Principal         Principal                           Realized
 Class            Amount               Balance          Distribution       Distribution        Accretion        Loss (3)
--------------------------------------------------------------------------------------------------------------------------
<S>          <C>                     <C>                <C>                <C>                 <C>              <C>
   A         1,080,076,000.00          948.32915686       0.00000000         15.83563301       0.00000000       0.00000000
  X-1                    0.00            0.00000000       0.00000000          0.00000000       0.00000000       0.00000000
  X-2                    0.00            0.00000000       0.00000000          0.00000000       0.00000000       0.00000000
  A-R                  100.00            0.00000000       0.00000000          0.00000000       0.00000000       0.00000000
  B-1           16,815,000.00         1000.00000000       0.00000000          0.00000000       0.00000000       0.00000000
  B-2            8,968,000.00         1000.00000000       0.00000000          0.00000000       0.00000000       0.00000000
  B-3            6,165,000.00         1000.00000000       0.00000000          0.00000000       0.00000000       0.00000000
  B-4            2,802,000.00         1000.00000000       0.00000000          0.00000000       0.00000000       0.00000000
  B-5            1,681,000.00         1000.00000000       0.00000000          0.00000000       0.00000000       0.00000000
  B-6            4,486,095.46         1000.00000000       0.00000000          0.00000000       0.00000000       0.00000000
--------------------------------------------------------------------------------------------------------------------------
</TABLE>

<TABLE>
<CAPTION>
----------------------------------------------------------------------------------------------
                                     Ending
             Total Principal       Certificate       Ending Certificate        Total Principal
 Class          Reduction            Balance             Percentage             Distribution
----------------------------------------------------------------------------------------------
<S>          <C>                   <C>               <C>                       <C>
   A             15.83563301        932.49352385             0.93249352            15.83563301
  X-1             0.00000000          0.00000000             0.00000000             0.00000000
  X-2             0.00000000          0.00000000             0.00000000             0.00000000
  A-R             0.00000000          0.00000000             0.00000000             0.00000000
  B-1             0.00000000       1000.00000000             1.00000000             0.00000000
  B-2             0.00000000       1000.00000000             1.00000000             0.00000000
  B-3             0.00000000       1000.00000000             1.00000000             0.00000000
  B-4             0.00000000       1000.00000000             1.00000000             0.00000000
  B-5             0.00000000       1000.00000000             1.00000000             0.00000000
  B-6             0.00000000       1000.00000000             1.00000000             0.00000000
----------------------------------------------------------------------------------------------
</TABLE>

(3) Amount does not include excess special hazard, bankruptcy, or fraud losses
unless otherwise disclosed. Please refer to the prospectus supplement for a full
description.
<PAGE>
                        INTEREST DISTRIBUTION STATEMENT

<TABLE>
<CAPTION>
---------------------------------------------------------------------------------------------------------------------------
                                                                                                 Payment of
                                                            Beginning            Current           Unpaid          Current
                Original Face          Current             Certificate/          Accrued          Interest        Interest
 Class              Amount         Certificate Rate      Notional Balance        Interest         Shortfall       Shortfall
---------------------------------------------------------------------------------------------------------------------------
<S>            <C>                 <C>                   <C>                   <C>               <C>              <C>
   A           1,080,076,000.00            1.55000%      1,024,267,562.43      1,323,012.27            0.00            0.00
  X-1                      0.00            1.06627%        242,142,066.19        215,158.13            0.00            0.00
  X-2                      0.00            1.16490%        798,940,496.24        775,571.68            0.00            0.00
  A-R                    100.00            3.16651%                  0.00              0.00            0.00            0.00
  B-1             16,815,000.00            1.95000%         16,815,000.00         27,324.38            0.00            0.00
  B-2              8,968,000.00            2.69842%          8,968,000.00         20,166.20            0.00            0.00
  B-3              6,165,000.00            2.69842%          6,165,000.00         13,863.14            0.00            0.00
  B-4              2,802,000.00            2.69842%          2,802,000.00          6,300.81            0.00            0.00
  B-5              1,681,000.00            2.69842%          1,681,000.00          3,780.04            0.00            0.00
  B-6              4,486,095.46            2.69842%          4,486,095.46         10,087.81            0.00            0.00
---------------------------------------------------------------------------------------------------------------------------
Totals         1,120,993,195.46                                                2,395,264.46            0.00            0.00
---------------------------------------------------------------------------------------------------------------------------
</TABLE>

<TABLE>
<CAPTION>
-----------------------------------------------------------------------------------------------
                Non-                                            Remaining            Ending
              Supported                                          Unpaid           Certificate/
              Interest       Realized     Total Interest        Interest           Notational
 Class        Shortfall      Loss (4)      Distribution         Shortfall           Balance
-----------------------------------------------------------------------------------------------
<S>           <C>            <C>          <C>                   <C>            <C>
   A               0.00          0.00       1,323,012.26             0.00      1,007,163,875.27
  X-1              0.00          0.00         215,158.13             0.00        239,705,205.53
  X-2              0.00          0.00         775,571.67             0.00        784,273,669.74
  A-R              0.00          0.00               0.00             0.00                  0.00
  B-1              0.00          0.00          27,324.37             0.00         16,815,000.00
  B-2              0.00          0.00          20,166.20             0.00          8,968,000.00
  B-3              0.00          0.00          13,863.14             0.00          6,165,000.00
  B-4              0.00          0.00           6,300.81             0.00          2,802,000.00
  B-5              0.00          0.00           3,780.04             0.00          1,681,000.00
  B-6              0.00          0.00          10,087.81             0.00          4,486,095.46
-----------------------------------------------------------------------------------------------
Totals             0.00          0.00       2,395,264.43             0.00
-----------------------------------------------------------------------------------------------
</TABLE>

(4) Amount does not include excess special hazard, bankruptcy, or fraud losses
unless otherwise disclosed. Please refer to the prospectus supplement for a full
description.

                    INTEREST DISTRIBUTION FACTORS STATEMENT

<TABLE>
<CAPTION>
-----------------------------------------------------------------------------------------------------------------------
                                                                                             Payment of
                                      Current          Beginning                               Unpaid         Current
                 Original Face      Certificate       Certificate       Current Accrued       Interest       Interest
Class (5)           Amount             Rate        Notional Balance         Interest          Shortfall      Shortfall
-----------------------------------------------------------------------------------------------------------------------
<S>             <C>                 <C>            <C>                  <C>                  <C>             <C>
    A           1,080,076,000.00      1.55000%         948.32915686          1.22492516       0.00000000     0.00000000
   X-1                      0.00      1.06627%         969.67625952          0.86161704       0.00000000     0.00000000
   X-2                      0.00      1.16490%         943.06244962          0.91547810       0.00000000     0.00000000
   A-R                    100.00      3.16651%           0.00000000          0.00000000       0.00000000     0.00000000
   B-1             16,815,000.00      1.95000%        1000.00000000          1.62500030       0.00000000     0.00000000
   B-2              8,968,000.00      2.69842%        1000.00000000          2.24868421       0.00000000     0.00000000
   B-3              6,165,000.00      2.69842%        1000.00000000          2.24868451       0.00000000     0.00000000
   B-4              2,802,000.00      2.69842%        1000.00000000          2.24868308       0.00000000     0.00000000
   B-5              1,681,000.00      2.69842%        1000.00000000          2.24868531       0.00000000     0.00000000
   B-6              4,486,095.46      2.69842%        1000.00000000          2.24868376       0.00000000     0.00000000
-----------------------------------------------------------------------------------------------------------------------
</TABLE>

<TABLE>
<CAPTION>
--------------------------------------------------------------------------------------------------------
                  Non-                                                Remaining
                Supported                                              Unpaid
                Interest           Realized        Total Interest     Interest       Ending Certificate/
Class (5)       Shortfall          Loss (6)         Distribution      Shortfall       Notational Balance
--------------------------------------------------------------------------------------------------------
<S>             <C>               <C>              <C>                <C>            <C>
    A           0.00000000        0.00000000           1.22492515     0.00000000            932.49352385
   X-1          0.00000000        0.00000000           0.86161704     0.00000000            959.91766628
   X-2          0.00000000        0.00000000           0.91547809     0.00000000            925.74985451
   A-R          0.00000000        0.00000000           0.00000000     0.00000000              0.00000000
   B-1          0.00000000        0.00000000           1.62499970     0.00000000           1000.00000000
   B-2          0.00000000        0.00000000           2.24868421     0.00000000           1000.00000000
   B-3          0.00000000        0.00000000           2.24868451     0.00000000           1000.00000000
   B-4          0.00000000        0.00000000           2.24868308     0.00000000           1000.00000000
   B-5          0.00000000        0.00000000           2.24868531     0.00000000           1000.00000000
   B-6          0.00000000        0.00000000           2.24868376     0.00000000           1000.00000000
--------------------------------------------------------------------------------------------------------
</TABLE>

(5) Per $1 denomination

(6) Amount does not include excess special hazard, bankruptcy, or fraud losses
unless otherwise disclosed. Please refer to the prospectus supplement for a full
description.
<PAGE>
                      CERTIFICATEHOLDER ACCOUNT STATEMENT

                              CERTIFICATE ACCOUNT

<TABLE>
<S>                                                             <C>
Beginning Balance

Deposits

           Payments of Interest and Principal                      19,834,799.27
           Liquidations, Insurance Proceeds, Reserve Funds                  0.00
           Proceeds from Repurchased Loans                                  0.00
           Other Amounts (Servicer Advances)                                0.00
           Realized Losses                                                  0.00
           Prepayment Penalties                                             0.00
                                                                ----------------
Total Deposits                                                     19,834,799.27

Withdrawals

           Reimbursement for Servicer Advances                            648.37
           Payment of Service Fee                                     335,199.29
           Payment of Interest and Principal                       19,498,951.61
                                                                ----------------
Total Withdrawals (Pool Distribution Amount)                       19,834,799.27

Ending Balance                                                              0.00
                                                                ================
</TABLE>

                   PREPAYMENT/CURTAILMENT INTEREST SHORTFALL

<TABLE>
<S>                                                             <C>
Total Prepayment/Curtailment Interest Shortfall                             0.00
Servicing Fee Support                                                       0.00
                                                                ----------------

Non-Supported Prepayment Curtailment Interest Shortfall                     0.00
                                                                ================
</TABLE>

                                 SERVICING FEES

<TABLE>
<S>                                                             <C>
Gross Servicing Fee                                                   335,199.29
Supported Prepayment/Curtailment Interest Shortfall                         0.00
                                                                ----------------

Net Servicing Fee                                                     335,199.29
                                                                ================
</TABLE>
<PAGE>
<TABLE>
<CAPTION>
                        Beginning        Current        Current         Ending
Account Type             Balance       Withdrawals      Deposits        Balance
--------------------------------------------------------------------------------
<S>                     <C>            <C>              <C>            <C>
Reserve Fund            10,000.00         0.00            0.00         10,000.00
</TABLE>

            LOAN STATUS STRATIFICATION/CREDIT ENHANCEMENT STATEMENT

<TABLE>
<CAPTION>
----------------------------------------------------------------------------------------------------------------------------------
                  DELINQUENT                                   BANKRUPTCY                               FORECLOSURE
----------------------------------------------------------------------------------------------------------------------------------
                   No. of        Principal                     No. of        Principal                    No. of       Principal
                   Loans          Balance                       Loans         Balance                     Loans         Balance
<S>              <C>             <C>            <C>           <C>            <C>          <C>           <C>            <C>
0-29 Days            0                    0.00  0-29 Days         0                 0.00  0-29 Days         0                 0.00
30 Days              0                    0.00  30 Days           0                 0.00  30 Days           0                 0.00
60 Days              0                    0.00  60 Days           0                 0.00  60 Days           0                 0.00
90 Days              0                    0.00  90 Days           0                 0.00  90 Days           0                 0.00
120 Days             0                    0.00  120 Days          0                 0.00  120 Days          0                 0.00
150 Days             0                    0.00  150 Days          0                 0.00  150 Days          0                 0.00
180+ Days            0                    0.00  180+ Days         0                 0.00  180+ Days         0                 0.00
                 -----------------------------                --------------------------                --------------------------
                     0                    0.00                    0                 0.00                    0                 0.00

                   No. of        Principal                     No. of        Principal                    No. of       Principal
                   Loans          Balance                       Loans         Balance                     Loans         Balance

0-29 Days        0.000000%       0.000000%      0-29 Days     0.000000%      0.000000%    0-29 Days     0.000000%      0.000000%
30 Days          0.000000%       0.000000%      30 Days       0.000000%      0.000000%    30 Days       0.000000%      0.000000%
60 Days          0.000000%       0.000000%      60 Days       0.000000%      0.000000%    60 Days       0.000000%      0.000000%
90 Days          0.000000%       0.000000%      90 Days       0.000000%      0.000000%    90 Days       0.000000%      0.000000%
120 Days         0.000000%       0.000000%      120 Days      0.000000%      0.000000%    120 Days      0.000000%      0.000000%
150 Days         0.000000%       0.000000%      150 Days      0.000000%      0.000000%    150 Days      0.000000%      0.000000%
180+ Days        0.000000%       0.000000%      180+ Days     0.000000%      0.000000%    180+ Days     0.000000%      0.000000%
                 -----------------------------                --------------------------                --------------------------
                 0.000000%       0.000000%                    0.000000%      0.000000%                  0.000000%      0.000000%
</TABLE>

<TABLE>
<CAPTION>
---------------------------------------------------------------------------------------
                   REO                                         TOTAL
---------------------------------------------------------------------------------------
                  No. of       Principal                   No. of         Principal
                  Loans         Balance                     Loans          Balance
<S>             <C>            <C>          <C>           <C>             <C>
0-29 Days           0                 0.00  0-29 Days         0                    0.00
30 Days             0                 0.00  30 Days           0                    0.00
60 Days             0                 0.00  60 Days           0                    0.00
90 Days             0                 0.00  90 Days           0                    0.00
120 Days            0                 0.00  120 Days          0                    0.00
150 Days            0                 0.00  150 Days          0                    0.00
180+ Days           0                 0.00  180+ Days         0                    0.00
                --------------------------                -----------------------------
                    0                 0.00                    0                    0.00

                  No. of       Principal                   No. of         Principal
                  Loans         Balance                     Loans          Balance

0-29 Days       0.000000%      0.000000%    0-29 Days     0.000000%       0.000000%
30 Days         0.000000%      0.000000%    30 Days       0.000000%       0.000000%
60 Days         0.000000%      0.000000%    60 Days       0.000000%       0.000000%
90 Days         0.000000%      0.000000%    90 Days       0.000000%       0.000000%
120 Days        0.000000%      0.000000%    120 Days      0.000000%       0.000000%
150 Days        0.000000%      0.000000%    150 Days      0.000000%       0.000000%
180+ Days       0.000000%      0.000000%    180+ Days     0.000000%       0.000000%
                --------------------------                -----------------------------
                0.000000%      0.000000%                  0.000000%       0.000000%
</TABLE>

Current Period Class A Insufficient Funds:                                  0.00

Principal Balance of Contaminated Properties                                0.00

Periodic Advance                                                            0.00

<TABLE>
<CAPTION>
                      Original $     Original %       Current $       Current %
<S>                 <C>              <C>            <C>              <C>
    Bankruptcy         218,860.00    0.01952376%       218,860.00    0.02088197%
         Fraud      33,629,796.00    3.00000001%    33,629,796.00    3.20870209%
Special Hazard      11,209,932.00    1.00000000%    10,480,809.71    1.00000000%
</TABLE>

Limit of subordinate's exposure to certain types of losses
<PAGE>
                              COLLATERAL STATEMENT

<TABLE>
<S>                                                             <C>
Collateral Description                                                 Mixed ARM

Weighted Average Gross Coupon                                          3.076046%
Weighted Average Net Coupon                                            2.698422%
Weighted Average Pass-Through Rate                                     2.698422%
Weighted Average Maturity (Stepdown Calculation)                             318

Beginning Scheduled Collateral Loan Count                                  3,045
Number of Loans Paid in Full                                                  45
Ending Scheduled Collateral Loan Count                                     3,000

Beginning Scheduled Collateral Balance                          1,065,184,657.89
Ending Scheduled Collateral Balance                             1,048,080,970.73
Ending Actual Collateral Balance at 31-July-2003                1,048,083,590.58

Monthly P&I Constant                                                2,730,463.73
Special Servicing Fee                                                       0.00
Prepayment Penalties                                                        0.00
Realization Loss Amount                                                     0.00
Cumulative Realized Loss                                                    0.00

Ending Scheduled Balance for Premium Loans                      1,048,080,970.73

Scheduled Principal                                                         0.00
Unscheduled Principal                                              17,103,687.16
</TABLE>

                            MISCELLANEOUS REPORTING

<TABLE>
<S>                                                               <C>
Principal Balance of 1-Month Libor Loans                          245,347,311.91
Principal Balance of 6-Month Libor Loans                          802,733,658.82
Pro Rata Senior Percentage                                            96.158685%
Senior Percentage                                                    100.000000%
Senior Prepayment Percentage                                         100.000000%
Subordinate Percentage                                                 0.000000%
Subordinate Prepayment Percentage                                      0.000000%
Payment Received from Cap Provide                                              0
</TABLE>