While the DBlib API will still work (for the most part) I strongly recommend that you migrate your code to something that is based on Client Library (i.e. Sybase::CTlib, or DBI/DBD::Sybase).
The reason: Sybase has not updated DBlib recently, and any changes in the TDS protocol in the 15.x code base is not available when using DBlib (e.g. longer identifier names, for example).