Random characters

Hi

I've took over a corporate network from the previous administrator recently. 
Everything appeared to work fine until this morning, now anything printed from 
Windows clients to the HP8150 through the CUPS server has a line of random 
characters at the top of the page. A test page from a linux client did not 
exhibit the same problem. 

Has anyone seen this before? 

Thanks!
Peter

PS. Are there any searchable archives of the cups mailing list?