ColdFusion: Error Passing Date that doesn't have day of week? - datetime

Question

I am trying to parse two date strings into date objects. The code works for one string, but throws an "invalid date time" error for the other. The only difference is that it's got a "Sat, " at the beginning! Please tell me why this is happening and how I can solve it!
<cfset datetimetest1 = "23 Nov 2013 00:53:12 +0000">
<!--- ^ This throws an error (when you try to pass it). Error says 'invalid date time' --->
<cfset datetimetest2 = "Sat, 23 Nov 2013 00:53:12 +0000">
<!--- ^ This works when it is parsed --->
<cfoutput>
#parsedatetime(datetimetest1)# #parsedatetime(datetimetest2)#
</cfoutput>

Answer 1

I identified RSS dates that are being used from the following sources and tested them against isDate(), DateFormat() and LSDateFormat(). ColdFusion 10,286680 was only able to parse 65% of the dates (38 out of 58).
http://rssdateformats.tumblr.com/
https://github.com/mjibson/goread/blob/0387db10bd9fd9ccd90d557fa30b6e494efa577a/goapp/utils.go#L129
Here's the test script that I wrote:
https://gist.github.com/JamoCA/7617349
I've been looking for a Java date parser library and recently found Natty and StringToTime, but haven't used either yet. (Neither resource provides a downloadable JAR file.):
http://natty.joestelmach.com/
https://github.com/collegeman/stringtotime

Answer 2

Update:
As of CF10+, you can use a custom format string to instruct the function on how to parse and convert the input into a datetime object:
// Custom format string
dateObject = parseDateTime("23 Nov 2013 00:53:12 +0000"
, "dd MMM yyyy HH:mm:ss zzz");
This is one area in which CF's flexibility and ease of use can be a disadvantage IMO. Unfortunately parseDateTime does not allow you specify the format of the input string, so CF has to do a lot of guessing to "automagically" convert your string into a date object.
One of the tools CF employs is java's SimpleDateFormat class, which utilizes patterns to parse or convert strings into Dates. My understanding is CF maintains a listing of standard date/time patterns (according to U.S. date conventions). Your first string must not match any of those patterns. Hence the error.
If your date strings are always in UTC, you could simply use list functions to omit the timezone offset ie +0000, then parse the string as usual:
<cfscript>
origString = "23 Nov 2013 00:53:12 +0000";
dateString = listFirst(origString, "+");
WriteDump(parseDateTime(dateString));
</cfscript>
Or you could DIY using SimpleDateFormat and the appropriate pattern dd MMM yyyy HH:mm:ss Z (see Date and Time Patterns). Just note the returned dates are in local time, so you may need to use DateConvert if you want UTC times:
// get formatter based on default locale
formatter = createObject("java", "java.text.SimpleDateFormat").init();
// set up pattern for input date string
formatter.applyPattern("dd MMM yyyy HH:mm:ss Z");
// parse it into a date object
dateObject = formatter.parse("23 Nov 2013 00:53:12 +0000");
// display result in local and UTC time
WriteDump("local="& dateObject);
WriteDump("utc="& DateConvert("local2UTC", dateObject));