Fatal error with date formatting on Safari

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Include date-functions.js in your script
2. Run the following
var test = new Date();
test.dateFormat("j M Y");

What is the expected output? What do you see instead?
Formatting to run with no errors.  Instead Safari conks out with the following 
error:
TypeError: Result of expression 'Date.monthNames[this.getMonth()]' [undefined] 
is not an object.

What version of the product are you using? On what operating system?
Safari 5.0.3
Mac OS X 10.6.5

Please provide any additional information below.

Original issue reported on code.google.com by [email protected] on 14 Jan 2011 at 4:22