I'm trying to use jquery corner to get curvy quicklaunch in my sharepoint 2010. But i geting eeor "object doesn't support this property or method. Any ideas if this version are compatible. Thanks in Advance
Odds are you haven't got the two references to the .js files right or in the right order. If you post your code we can verify this, but usually that error indicates an incorrect reference.
I recognize that this might not exactly be the answer you are looking for, but for such a simple task I'd try to avoid complex and error prone scripting solutions.
Update: Corrected the code due to a bug in the previous version and added a red border for better readability.
Instead I'd go with a simple CSS 3 solution which is supported by all modern Web browser like Mozilla Firefox, Google Chrome/Chromium, Apple Safari and Opera. As for Internet Explorer it is supported with IE 9+ (with a change in your masterpage of "X-UA-Compatible" to "IE=8;IE=EmulateIE9").
In this scenario the CSS would look like:
However, if you need to support legacy Web browsers like IE 8 and below I'd rather use CSS3 Pie http://css3pie.com/ instead of jQuery, like this:
CSS3 Pie is an awesome library to bring several missing CSS 3 features to IE and I'm using it frequently to overcome several IE limitations without requiring scripting hacks.
Hope that helps!