proxy setup

[Istvan Gabor]

Hello:

My FreeBSD 9.0-RELEASE system is behind a institutional firewall.
Obviously I can not change any settings of this firewall.
After installing FreeBSD and not setting any proxy servers I could install
packages using pkg_add -r command.
But when I tried to update the system freebsd-update fetch stopped.
I traced that it stopped because getting the file through ftp failed:
(with "failed: Connection refused: messages").
Therefore I have set http_proxy and ftp_proxy variables in my .profile file.
After this the update ran without any problem.
But now pkg_add -r refuses to fetch files with message:
Error: Unable to get ftp://ftp.freebsd.org/pub/FreeBSD....: Forbidden
wget with --no-proxy option can fetch the file, that is the problem 
for pkg_add is probably the configured http or ftp proxy.
How can fix this so that I should not every time set/unset proxy when
I want to update the system or install a package?

Thanks,

Istvan