Using BM 3.8 sp2, IE 6 with Show friendly errors off. All HTTP traffic
through Proxy.

Currently when a web problem occurs the user receives a 502 bad gateway
from the proxy server.

The error message in the IIS server logs is much more specific and really
describes what is happening
How can I get the message to the user?

Sample from IIS log
POST /load.asp |262|80040e14|[Microsoft][ODBC_SQL_Server_Driver]
Procedure_'sp_testing_testinghistory_v1'_expects_p arameter_'@make'__which_w
as_not_supplied. 500 Mozilla/4.0+(compatible;+MSIE+6.0;+Windows+NT+5.1)