<TABLE> <S> <C>

<PAGE>
<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS RESTATED SUMMARY FINANCIAL INFORMATION EXTRACTED FROM 
THE RESPECTIVE BALANCE SHEETS AS OF DEC-31-1996, MAR-31-1997, JUN-30-1997,
SEP-30-1997 AND THE RELATED STATEMENTS OF INCOME AND CASH FLOWS FOR THE 
RESPECTIVE PERIODS THEN ENDED.
</LEGEND>
<RESTATED> 
<MULTIPLIER> 1,000
       
<S>                             <C>                     <C>                     <C>                     <C>
<PERIOD-TYPE>                   YEAR                    3-MOS                   6-MOS                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1996             DEC-31-1997             DEC-31-1997             DEC-31-1997
<PERIOD-START>                             JAN-01-1996             JAN-01-1997             JAN-01-1997             JAN-01-1997
<PERIOD-END>                               DEC-31-1996             MAR-31-1997             JUN-30-1997             SEP-30-1997
<CASH>                                          19,801                  19,851                  22,005                  17,224
<SECURITIES>                                         0                       0                       0                       0
<RECEIVABLES>                                    6,011                   6,278                   6,371                   5,672
<ALLOWANCES>                                       433                     378                     439                     449
<INVENTORY>                                          0                       0                       0                       0
<CURRENT-ASSETS>                                25,869                  26,263                  28,380                  23,001
<PP&E>                                           3,805                   3,869                   4,365                   5,130
<DEPRECIATION>                                   1,943                   1,930                   2,122                   2,522
<TOTAL-ASSETS>                                  28,700                  29,191                  31,879                  36,523
<CURRENT-LIABILITIES>                            8,633                   7,817                   8,458                  12,105
<BONDS>                                              0                       0                       0                       0
<PREFERRED-MANDATORY>                                0                       0                       0                       0
<PREFERRED>                                          0                       0                       0                       0
<COMMON>                                           141                     141                     143                     148
<OTHER-SE>                                      19,010                  20,217                  22,371                  22,428
<TOTAL-LIABILITY-AND-EQUITY>                    28,700                  29,191                  31,879                  36,523
<SALES>                                              0                       0                       0                       0
<TOTAL-REVENUES>                                20,314                   6,520                  13,700                  21,609
<CGS>                                                0                       0                       0                       0
<TOTAL-COSTS>                                    1,039                     295                     601                     991
<OTHER-EXPENSES>                                18,374                   5,163                  10,303                  27,712
<LOSS-PROVISION>                                     3                       0                      60                     120
<INTEREST-EXPENSE>                                 101                       7                       9                      10
<INCOME-PRETAX>                                  1,018                   1,273                   3,236                   (739)
<INCOME-TAX>                                     (245)                      80                     180                     713
<INCOME-CONTINUING>                              1,263                   1,193                   3,056                 (1,452)
<DISCONTINUED>                                       0                       0                       0                       0
<EXTRAORDINARY>                                      0                       0                       0                       0
<CHANGES>                                            0                       0                       0                       0
<NET-INCOME>                                     1,263                   1,193                   3,056                 (1,452)
<EPS-PRIMARY>                                     0.10                    0.09                    0.22                  (0.10)
<EPS-DILUTED>                                     0.10                    0.08                    0.20                  (0.10)
        


</TABLE>