Browser snifffing using Blackberry

Question

Am facing an issue regarding downloading a Blackberry app file(JAD/COD file) through OTA(over internet).The problem scenario is like below.

While trying to download from Blackberry device using GPRS(external public network),it returns HTTP 500(it’s a server side error nothing related to Blackberry device). If I also uploaded the same BB app files in our Mobile CoE public IIS 6.0 server and able to download from BB device. I would request your help to solve this issue.

The error i was getting is HTTP 500 with Error Code 10061: Connection refused .HTTP 500 is a server side generic error.