[Gimp-user] Does GIMP allow cropping using a NUMERICAL pixel value for crop depth?

["Eric Scharf" <waverley2007 tiscali co uk>]

Dear GIMP users,

Is it possible to express for an image (PNG, JPG etc) the cropping depth 
(for each of top, bottom, left, right) in terms of an EXACT number of 
pixels?

This would be VERY useful for preparing images for web pages, where required 
cursor access is given in terms of (X ,Y) pixels. The GIMP cursor based crop 
mask - useful as it may be - is not really up to this particular precision 
requirement.

In advance of some insight,

Many Thanks,

Eric Scharf (waverley2007 tiscali co uk)