i've done a little snooping around in font-lock to see what coud be causing this problem (affects only VM for me). in font-lock-default-fontify-buffer, there is a call to unfontify-region followed by a fontify-region. (font-lock-unfontify-region (point-min) (point-max)) ... (font-lock-fontify-region (point-min) (point-max) ) i played around with commenting out each or both of these calls. case: both commented out: no infinite loop AND VM digest IS properly fontifed ANYWAY of course, things like C files get NO fontification both left on: infinite loop in unfontify-region call unfontify commented out: infinite loop in fontify-region call fontify commented out: infinite loop in unfontify-region call VM digest IS properly fontifed anyway upon breaking out of loop les schaffer