printing: "lp: unable to create temporary file."

[igoldtho]

I don't know if this is the right place to post this but ...

I have set up cups and, as an unprivileged user, am not able to print directly from applications and if I try:
echo "test string" | lp
I get the following message:
lp: unable to create temporary file.

I am able to print using this command format:
lp filename
As a work-around most applications can print to file and the file can be printed from the command line.

If I am root, printing works perfectly.

It is obviously a permission problem but I don't know where the temporary file should be created.

I have added my user to the group "lp" but it has not helped.

Can anyone tell me the proper way to correct the problem?