locale egg fails when TZ is "UTC"

[John Foerch]

In a cgi program called through Apache, I get the following error when I (use locale):

bad timezone STD offset: "UTC"

Source of the error is the function parse-posix-literal-timezone, where offset-re fails to match. If I change the environment variable TZ to "UTC+0" in my .htaccess, there is no error.

Relevant system information:

$ cat /etc/debian_version
6.0.1
$ chicken-status|grep -m1 locale
locale .......................... version: 0.6.12
$ csc -V
(c)2008-2010 The Chicken Team
(c)2000-2007 Felix L. Winkelmann
Version 4.5.0
linux-unix-gnu-x86 [ manyargs dload ptables ]
compiled 2010-06-17 on biber (Linux)

Also reproduced with Chicken 4.7 on another system by calling (parse-posix-literal-timezone "UTC") directly from a repl. (I had no trouble loading the locale egg on that other system.)

[Kon Lovett]

Not sure what to do about this. TZ=FOO is ambiguous, what offset should be assumed?

POSIX.1 specifies "std offset" (& "std offset dst [offset],starttime,endtime") where the offset is required. So TZ=UTC+0 is the correct form.