Tool that would allow you to rename schema name can be found as Mscrmrenameattributes.exe along with CRM 3.0 rollup update install. Unfortunately, i am not sure if Microsoft provides this as a seperate one.
Key issues that are fixed in Update Rollup 2 for Microsoft Dynamics CRM 3.0
918990 (http://support.microsoft.com/kb/918990/) You experience timeouts or slow performance after you change a security role or after you import a customization file in Microsoft Dynamics CRM 3.0
920135 (http://support.microsoft.com/kb/920135/) Error message when you try to import a customization into Microsoft Dynamics CRM 3.0: "The selected customization file does not conform to the required customization file schema"
920859 (http://support.microsoft.com/kb/920859/) Error message when you send an e-mail message in Microsoft Dynamics CRM 3.0: "You do not have enough privileges to access the Microsoft CRM Object or perform the requested operation"
921065 (http://support.microsoft.com/kb/921065/) Internet Information Services stops responding on a Microsoft Dynamics CRM 3.0 server
921235 (http://support.microsoft.com/kb/921235/) You experience timeouts or slow performance when you reassign records from one user to another user in Microsoft Dynamics CRM 3.0
923281 (http://support.microsoft.com/kb/923281/) The client stops responding when you try to go offline or to run the "Synchronize Outlook with CRM" function in Microsoft Dynamics CRM client for Outlook
925437 (http://support.microsoft.com/kb/925437/) Error message when you send an e-mail message from the Microsoft Dynamics CRM 3.0 Web client: "Insufficient Permissions"
925505 (http://support.microsoft.com/kb/925505/) Microsoft Outlook stops responding when you click a command button on the Microsoft Dynamics CRM toolbar
925874 (http://support.microsoft.com/kb/925874/) An update for the 2007 daylight saving time changes is available for Microsoft Dynamics CRM 3.0 and for the Microsoft Dynamics CRM 3.0 client for Outlook
928272 (http://support.microsoft.com/kb/928272/) Outlook exits unexpectedly when you click "Go Offline" in the Microsoft Dynamics CRM laptop client for Outlook
929488 (http://support.microsoft.com/kb/929488/) Error message when you attach a .docx file to a record in Microsoft Dynamics CRM 3.0: "File Upload Failure"
931270 (http://support.microsoft.com/kb/931270/) Error message when you use the Microsoft Dynamics CRM client for Microsoft Office Outlook: "Microsoft Office Outlook has encountered a problem and needs to close. We are sorry for the inconvenience"
932984 (http://support.microsoft.com/kb/932984/) How to make the 2007 daylight saving time changes by using the Update Time Zones Wizard for Microsoft Dynamics CRM 3.0
for details visit - http://support.microsoft.com/default.aspx?kbid=927751
Download rollup 2 update for MS CRM 3.0 server here -
* CRM3.0-KB927751-Server-ENU.exe package - http://www.microsoft.com/downloads/details.aspx?FamilyId=81674DA5-FFEF-492A-A7B1-7E1F1951B05F
Download CRM 3.0 client for Microsoft Office Outlook here -
* CRM3.0-KB927751-Client-ENU.exe package - http://www.microsoft.com/downloads/details.aspx?FamilyId=81674DA5-FFEF-492A-A7B1-7E1F1951B05F