Multi-thread client support in databses like infomix, sybase...

I have a question for all the database wizards. Are there any databases around which can support a process with multiple threads? We bought informix and got stuck with it. It cannot support a multi-threaded client. Informix has an SQL server which is multi-threaded, and each thread looks after a process. But it cannot handle a process with multiple threads making several database calls simultaneously - ALL BECAUSE OF ONE REASON: dumb sqlca structure and non-reentrant database libraries. It seems that there is a global structure "sqlca" which returns the results of a database transaction. So, if you try to perform two operations at the same time, this structure will get currupted. Can anyone tell me a reason to do this? I would assume a neater and sensible way to do this would be to allow the programmer to define a structure of type "sqlca" and pass a pointer to it to database routines. The database returns values in this structure. Thanks, Pawan