Good question. Looks like SPR 640852 "Direct EPDM Web Client local cache to a shorter path or allow the local cache to be created at a specified location" is open, so answer is no.
I would like to assume there's a registry key storing this value but am not sure.
The easiest way is to install the thick client of EPDM, If EPDM client is installed and with a local view, the web client will use this path to cache files.
If you cannot or do not wish to install the normal EPDM client, you can change it manually with a few steps, one of witch is changing a registry key.
Contact your local var to assist you in getting access to this information.
Does KB article S-014164 have any value to you?
My VAR sent me the instructions (5 page pdf) and I got it working. Today was the first time I've needed it. Thanks