Forms doesn't launch from self service

Srinivas contacted me about this issue today.  After converting an instance into shared application file system aka shared APPL_TOP, forms were not launching from self service.

I opened a putty session in one window and tailed the apache access log.  On another window I opened Internet Explorer and arranged both side by side.  I logged in successfully. The OA framework page showing responsibilities came up.  I chose System Administrator and clicked on Concurrent Requests.  Internet Explorer stopped there progress bar froze at midway.  Apache access log showed HTTP-403:

192.168.122.10 - - [02/Apr/2009:18:12:03 -0400] "GET /pls/apps11i/fnd_icx_launch.launch?resp_app=SYSADMIN&resp_key=SYSTEM_ADMINISTRATOR&secgrp_key=STANDARD&start_func=FND_FNDCPQCR_SYS&other_params= HTTP/1.1" 403 244 0

I checked the $IAS_CONFIG_HOME/Apache/Apache/conf/httpd_pls.conf file and found these lines:

Allow from apps11i.justanexample.dev.com

This was incorrect.  It should have been:

Allow from apps11i.dev.justanexample.com

Once I corrected this and bounced Apache, no more HTTP-403 errors appeared and forms launched correctly