In MatrixCellEntityProviderImpl.java. The redirect url is hardcoded to /portal/ when it should be getting it from the configuration file.
We use the xsl-portal so this was causing issues when the user would request feedback from within a cell. The Evaluator would click the link and take them to the matrices tool page instead of the cell to provide feedback.
Attached is a patch that get's the path from the sakai.properties