Andreas, thank you for the info.
The Intersolv driver manager is looking for the Sybase database library that had been provided with Sybase OS/2 clients prior to System 10, specifically SYBDB.DLL, the 32-bit version of the library.
In the past, I believe the OS/2 client could be freely downloaded from Sybase, but I am unable to find it available for download anywhere on the Net.