I use GnuPG 1.4.5, Thunderbird 1.5.0.5, Enigmail 0.94.1, and Windows XP Pro SP2.
I composed a message in Thunderbird, with word wrap disabled. After the
message was sent, the result was double spacing in the ASCII-armored PGP output.

GnuPG/OpenPGP was unable to decrypt the message I had sent. However, my
recipient, who uses the commercial version of PGP, was able to decrypt it.
Below is what GnuPG reports when decryption is attempted, and attached is the
PGP message itself.

gpg command line and output:
C:\Program Files\GnuPG\gpg.exe --charset utf8 --batch --no-tty --status-fd 2 -d
--passphrase-fd 0 --no-use-agent

gpg: invalid radix64 character 3A skipped
gpg: invalid radix64 character 2D skipped
gpg: invalid radix64 character 2D skipped
gpg: invalid radix64 character 3A skipped
gpg: invalid radix64 character 3A skipped
gpg: invalid radix64 character 2E skipped
gpg: invalid radix64 character 2E skipped
gpg: CRC error; F534D7 - F1FCD7
gpg: [don't know]: invalid packet (ctb=0a)