What's wrong with php_mssql70.dll and PHP4?

Hi!: I don't know if this issue has been discussed here lately, I'm just new to the list. I tried to compile the IIS module php_mssql70.dll with the PHP4 source files. I couldn't find some headers there ("sqlfront.h" and "sqldb.h") so I used the ones from php3 source code. It compiled (!), and loaded, I even opened a connection but every time I make a mssql_query I get an error from PHP (something like an Access Violation). So I'm afraid it was not a very good idea to use those php3 headers in php4 compilation... Then I downloaded the binary .DLL from http://download.swwwing.com/php4/modules/ but, as it has been discussed lately in www.phpbuilder.com, it doesn't seem to load properly. Has anybody worked properly with php4 and php_mssql70.dll? In case nobody knows, I think I'll have to go back to php3... thanks in advance, F.J. Ortiz