Upgrade to bug fix release v0.22
+ Include the existing -x flag in the help message (Mark Hills)
+ Detect a trailing -f or -o with no following argument
+ Display message-ID in search -x mode
+ Skip symlinks when using mbox (R A Lichtensteiger)
+ Improve error message if home directory cannot be determined
+ Honour HOME environment variable (Andreas Amann)
+ MIME types are allowed to have "+" characters in them. (Jonathan Kamens)
+ Fix deficiencies in the parsing of mbox From lines (Jonathan Kamens)
+ Fix documentation nits (Tom Doherty)
+ Remove spurious message when the mtime of a message file has changed
+ Initialize the date header with a known value. (Samuel Tardieu)
+ Merge two conflicting solutions for bad MIME encoding
+ fix for MIME-related crash (Paramjit Oberoi)
+ Add support claws-mail (Anand Kumria)
+ Add MH sub-type support for ezmlm-archives (Claus Alboege)
+ Allow lines starting "From" to occur part-way through the header.o
+ Handle mbox from separators where email address is in angle brackets
+ Fix a bug in rfc822.c: Some headers weren't correctly parsed. (Jaime Velasco Juan)