I need to be able to call a sql server stored procedure from Sybase and eventually from DB2 as well (possibly others in the future). Does anyone have any experience doing this or know how it can be accomplished?

At 1 location we have cobol programs running on UNIX box that communicate with Sybase( also running on UNIX). Our 3rd party tax software ONLY runs on sql server. So we would like to be able to call a stored proc from sybase to communicate with a stored proc on sql server.