I found this in the packaged version of coreutils 8.13 on Debian 7 (currently still in beta), then verified it on a local build of coreutils 8.20.

Per my reading of the Wikipedia article on ISO 8601 (https://en.wikipedia.org/w/index.php?title=ISO_8601&oldid=521173253), these two date strings should both be valid and both represent the same date:

20121113T1200
2012-11-13T12:00

Yet when I pass them both to "date -d" I get different results (the short form gives an unexpected result; the expanded form is correct).  If I replace the 'T' with a space, "date -d" gives me the expected result for both forms.

$ src/date -d "20121113T1200"
Mon Nov 12 21:00:00 PST 2012
$ src/date -d "20121113 1200"
Tue Nov 13 12:00:00 PST 2012
$ src/date -d "2012-11-13 12:00"
Tue Nov 13 12:00:00 PST 2012
$ src/date -d "2012-11-13T12:00"
Tue Nov 13 12:00:00 PST 2012
$ src/date --version
date (GNU coreutils) 8.20
Copyright (C) 2012 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by David MacKenzie.
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