Seamonkey 2.0.1. installation fails since the script cannot locate the MD5 sum for the downloaded .tar.bz2 file.
This is because file names in the 2.0.1 MD5SUMS file do not begin with "./", unlike in earlier MD5SUMS files.
This bug has been fixed earlier today with the latest ubuntuzilla release (4.8.3)
Please upgrade to the latest version and give it another go.
(and by the way, thanks for your problem diagnosis - i appreciate the effort, even though it is a little late :) ).
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