Courtesy of the fine folks at Computas, there is a version of GemConnect for Sybase version 1.1.1 modified to coexist with GemConnect for Oracle 2.2 on 64-bit servers running GemStone/S 64. A makefile and library file for CentOS / Red Hat Linux is included.
Give it a try!
http://sourceforge.net/projects/gemconnsyb1ora2/
as always, further contributions and enhancements are welcome.
-- Monty