I am new to DSpace.  A former database designer/programmer, I can follow DSpace documentation reasonably well, but have no particular DSpace (or related software) skills otherwise. 

After satisfactory testing with version 1.8.2, I upgraded to 3.0, following instructions in the manual. Upgrade seemed OK, but I get the following on attempting to launch the Mirage XMLUI.

HTTP Status 404 - Servlet spring is not available
type Status report
message Servlet spring is not available
description The requested resource (Servlet spring is not available) is not available.

OS:            Mac OS X 10.7.5 (Lion)
DSpace:        3.0
Apache Tomcat: 7.0.27
Java:          1.6.0_37
Apache Maven:  3.0.3
Ant:           1.8.2

I've searched DSpace mailing lists, but without useful results so far. As suggested at https://wiki.duraspace.org/display/DSPACE/Troubleshoot+an+error ,
I've enabled DEBUGing in log files, but don't see any obvious source of the error.  I'm happy to provide logs if they would be helpful.

I would appreciate any suggestions.