http://rexxdw.sourceforge.net/
"Rexx/DW provides Rexx programmers with a lightweight, cross-platform GUI package. Rexx/DW uses Dynamic Windows to provide the cross-platform GUI that runs natively on Windows, OS/2 and GTK+."
OS/2 Download:
http://prdownloads.sourceforge.net/rexxdw/rexxdw10RC1os2.zip Other downloads including source can be found at
http://prdownloads.sourceforge.net/rexxdw
Support mailing lists can be found for this project at
http://sourceforge.net/projects/rexxdw/
Source: OS2VOICE