While it's possible to build the Apache Server for OS/2 yourself, doing so requires you to download and install a whole swag of GNU utilities as well as EMX GCC. If you really want to do this see Building Apache for OS/2.
With the release of Apache Server v1.3.9, loadable modules are now supported in OS/2 which means that there is no longer any need for multiple binaries compiled with different sets of modules. You just have to edit your httpd.conf file to load the modules you want at run time.
The normal Apache OS/2 binary distribution contains all the standard modules. You can also load third party modules as they become available.
Also available is Apache HTTP Server v2.0 which was released for general availability on the 5th April 2002.
Other items of interest to Apache for OS/2 users
While I've done much of the hard work by getting the thing compiled, installation is still not going to be a no-brainer. Please don't send me any questions on configuring Apache. The Apache distribution includes a manual which should be the place you go if you have questions.
SET EMXOPT=-h256 -!0x800" to your config.sys or apache start up script. This increases the number of file handles and activates a workaround for a file handle leak.
httpd -d c:\apps\apache
#!perland ensure that perl.exe is on your path. Alternatively you can specify the full path of the interpreter in the #! line.
PassEnv DPATHto your httpd.conf.
PassEnv ETCto your httpd.conf.