SQL2000 problem

Hiya all :o) My system is win2k (IIS5) with sql2k and php4 If I un-remark the line ;extension=php_mssql70.dll in the php.ini then on the first access of a mssql function, inetinfo hangs using 99 of processor time. Re-remark that line, and all is ok (except there is no mssql functions). Am I right in thinking that php_mssql70.dll is incompatable with sql2000? If this is the case, is there such an extension as php_mssql2k.dll (or similar) Any help would be very greatfully received, yours db-less marcus :o)