Copyright 2007 TeX Users Group.
You may freely use, modify and/or distribute this file.

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Checksum mismatches in DVIPS when using scalable outline fonts:
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DVIPS sometimes throws up spurious `checksum mismatch' messages when using
fonts other than bitmapped (PK) fonts.

These are often benign error messages that you can ignore (but see below).
You can suppress them in several ways, the easiest of which is to zero out
the checksum in the TFM files (e.g. by running the TFM file through TFtoPL,
editing the checksum field, and then running the PL file back through PLtoTF
--- or by using an editor on the TFM file and zeroing out bytes 24, 25, 26,
and 27).

DVIPS was originally designed for bitmapped fonts, where matching TFM metric
files with PK bitmapped font files is important.  This is why it matches the
checksum from the TFM file with the checksum in the corresponding PK font
file.  The checksum from the TFM file is recorded in the DVI file for each
font used.  The checksum in this case is computed by METAFONT.

In the case of scalable outline fonts, DVIPS/AFM2TFM uses a different
checksum hashing algorithm that is specific to that software.  What is more,
this algorithm has changed over the years, so that TFM files made some time
ago with AFM2TFM may no longer match what DVIPS computes today.

There is *one* situation where checksum mismatches in DVIPS are actually
significant and you'd want to check for this.  DVIPS is unique in reading TFM
files (other drivers assume that the font knows it own metrics).  If the TFM
file that DVIPS sees does not match the TFM file that TeX sees, you will get
such a mismatch.

This can be a symptom of a serious problem.  For example, the TFM files that
DVIPS sees may be set up for different encoding than those that your TeX
sees.  In this case the metrics of some characters will be corrupted since
DVIPS overwrites the advance widths of the actual font.  

*	So you should check that DVIPS is looking at the same TFM
	files as your TeX is.