Squid and relitive links?

In using Squid 3.6 as a reverse proxy (http acceleration), some relative
links show up fine (with the full http://... address), while others
show up as just /folder/file.txt with no http://, which in turn causes
an error. Has any one seen this and know if there are any settings in
squid.conf to fix it. (Nothing is being cached)

I know, you can set absolute paths in the html code. But the site is a
portal running on an IBM AS400 and I don't have authorization to dig
into it, yet...

Thanks for any help