According to http://www.os2.jp ACTIVATE ver 1.42 for OS/2 has been released. This is a command line utility for batch files to change windows to and from an active state. The documentation is in Japanese, but the program use appears to be in English.
English Translation of Japanese documentation:
http://www.excite.co.jp/world/english/web/body?wb_url=http%3A%2F%2Fhp.vector.co.jp%2Fauthors%2FVA023499%2Fsoft%2Factivate%2Factivate.html&wb_lp=JAEN&wb_d
Download: http://www.vector.co.jp/download/file/os2/util/fh471798.html
From: Mark Dodel
Source: OS2VOICE.org