Satellite 5.3: RHN API call errata.listPackages too slow (much slower than 4.2)

Issue

• upgraded RHN Satellite from 4.2 to 5.3 and migrated API scripts, one of which calls "errata.listPackages" RHN API method on the server
• made some tests using it, in both server(4.2 and 5.3), and I faced a big difference between Satellite 4.2 and 5.3 servers -

RHN 4.2: 5 seconds to run.
RHN 5.3: 10 minute to run.

Check bellow:

$ time ./pkgsrhn42.py
real 0m5.480s
$ time ./pkgrhn53.py
real 1m0.509s

• /var/log/rhn/rhn_web_api.log on 5.3 Satellie shows the folowing when running the command:

[2010-08-03 16:15:36,772] INFO  - REQUESTED FROM: *callerIp* CALL: user.listUsers(13646168x776a47cb1a522f15a4d2002a44384728) CALLER:  TIME: 90.323 seconds