<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-31-1996             MAR-31-1997             MAR-31-1997             MAR-31-1996
<PERIOD-START>                             APR-01-1995             OCT-01-1996             JUL-01-1996             APR-01-1996
<PERIOD-END>                               MAR-31-1996             DEC-31-1996             SEP-30-1996             JUN-30-1996
<CASH>                                          35,081                  30,991                  25,439                  29,015
<SECURITIES>                                     6,236                  12,194                  14,274                  13,273
<RECEIVABLES>                                   11,590                  17,612                  13,783                   9,385
<ALLOWANCES>                                       531                     946                     636                     510
<INVENTORY>                                          0                       0                       0                       0
<CURRENT-ASSETS>                                53,215                  60,767                  53,990                  51,878
<PP&E>                                           6,060                   9,299                   8,380                   7,289
<DEPRECIATION>                                   2,157                   3,945                   3,277                   2,651
<TOTAL-ASSETS>                                  57,291                  66,371                  59,343                  56,736
<CURRENT-LIABILITIES>                           13,501                  18,545                  14,776                  12,977
<BONDS>                                              0                       0                       0                       0
<PREFERRED-MANDATORY>                                0                       0                       0                       0
<PREFERRED>                                          0                       0                       0                       0
<COMMON>                                           183                     186                     184                     183
<OTHER-SE>                                      39,861                  45,877                  41,615                  40,266
<TOTAL-LIABILITY-AND-EQUITY>                    57,291                  66,371                  59,343                  56,736
<SALES>                                         30,045                  17,573                  14,214                  11,680
<TOTAL-REVENUES>                                30,045                  17,573                  14,214                  11,680
<CGS>                                            5,908                   3,439                   2,670                   2,516
<TOTAL-COSTS>                                   20,968                  11,136                   9,271                   8,281
<OTHER-EXPENSES>                                11,237                   4,034                   3,813                   3,563
<LOSS-PROVISION>                                     0                       0                       0                       0
<INTEREST-EXPENSE>                               (286)                   (488)                   (520)                   (489)
<INCOME-PRETAX>                                (1,874)                   2,891                   1,650                     325
<INCOME-TAX>                                       114                     342                     205                      32
<INCOME-CONTINUING>                            (1,988)                   2,549                   1,445                     293
<DISCONTINUED>                                       0                       0                       0                       0
<EXTRAORDINARY>                                      0                       0                       0                       0
<CHANGES>                                            0                       0                       0                       0
<NET-INCOME>                                   (1,988)                   2,549                   1,445                     293
<EPS-PRIMARY>                                   (0.41)                    0.14                    0.08                    0.02
<EPS-DILUTED>                                   (0.41)                    0.12                    0.07                    0.01
        

</TABLE>