HTTP 500 error when users delete objects to include documents, lists, and Webs

Cumulative update packages for Microsoft SharePoint Foundation 2010 contain hotfixes for the SharePoint Foundation 2010 issues that were fixed since the release of SharePoint Foundation 2010.

Note This is build 14.0.6120.5006 of the cumulative update package.

UpdateA recent, isolated issue was discovered in the SharePoint 2010 Products April 2012 Cumulative Update that could result in an HTTP 500 error when users delete objects to include documents, lists, and Webs and a new object is created using the same path where the original object remains in the Recycle Bin. The following packages were affected:

KB2598151 - SharePoint Server Package
KB2598152 - Project Server Package
KB2598321 - SharePoint Foundation Package
KB2598304 – Wss-x-none.msp

Resolution
This issue has been resolved in the revised packages. The revised packages include support for resolving issues related to the originally published updates.

Products Affected
SharePoint Foundation 2010
SharePoint Server 2010

reference : http://support.microsoft.com/kb/2598321