<TABLE> <S> <C>

<PAGE>
<ARTICLE> 5
<RESTATED> 
<MULTIPLIER> 1,000
       
<S>                             <C>                     <C>                     <C>                     <C>
<PERIOD-TYPE>                   YEAR                    3-MOS                   3-MOS                   3-MOS
<FISCAL-YEAR-END>                          MAR-31-1997             MAR-31-1998             MAR-31-1998             MAR-31-1998
<PERIOD-START>                             APR-01-1996             OCT-01-1997              JUL-1-1997             APR-01-1997
<PERIOD-END>                               MAR-31-1997             DEC-31-1997             SEP-30-1997             JUN-30-1997
<CASH>                                          35,103                  23,091                  24,349                  25,035
<SECURITIES>                                    13,154                  13,072                  15,294                  17,547
<RECEIVABLES>                                   18,691                  17,211                  18,120                  17,379
<ALLOWANCES>                                       941                   1,034                     969                   1,175
<INVENTORY>                                          0                       0                       0                       0
<CURRENT-ASSETS>                                67,010                  54,135                  58,919                  60,240
<PP&E>                                          11,122                  14,964                  13,750                  12,326
<DEPRECIATION>                                   4,633                   7,589                   6,512                   5,517
<TOTAL-ASSETS>                                  73,749                  61,910                  66,457                  67,299
<CURRENT-LIABILITIES>                           23,355                  21,411                  20,580                  18,179
<BONDS>                                              0                       0                       0                       0
<PREFERRED-MANDATORY>                                0                       0                       0                       0
<PREFERRED>                                          0                       0                       0                       0
<COMMON>                                           188                     195                     193                     193
<OTHER-SE>                                      48,486                  39,752                  44,945                  47,807
<TOTAL-LIABILITY-AND-EQUITY>                    73,149                  61,910                  66,457                  67,299
<SALES>                                         63,051                  17,345                  17,488                  14,674
<TOTAL-REVENUES>                                63,051                  17,345                  17,488                  14,674
<CGS>                                           12,461                   5,094                   4,680                   4,198
<TOTAL-COSTS>                                   41,021                  17,459                  15,432                  13,455
<OTHER-EXPENSES>                                15,730                   6,007                   5,574                   4,593
<LOSS-PROVISION>                                     0                        0                       0                       0
<INTEREST-EXPENSE>                             (1,988)                   (462)                   (515)                   (553)
<INCOME-PRETAX>                                  8,288                 (5,659)                 (3,003)                 (2,821)
<INCOME-TAX>                                     1,039                     630                    (20)                   (575)
<INCOME-CONTINUING>                              7,249                 (6,289)                 (2,983)                 (2,246)
<DISCONTINUED>                                       0                       0                       0                       0
<EXTRAORDINARY>                                      0                       0                       0                       0
<CHANGES>                                            0                       0                       0                       0
<NET-INCOME>                                     7,249                 (6,289)                 (2,983)                 (2,246)
<EPS-PRIMARY>                                     0.39                  (0.32)                  (0.15)                  (0.12)
<EPS-DILUTED>                                     0.34                  (0.32)                  (0.15)                  (0.12)
        

</TABLE>