Omeka_Validate_Exception while saving tags

Some of our users encountered a Omeka_Validate_Exception while saving an item.

I figured out that this is due to the way tags are saved. These users prepare a list of tags in an external document (word or some other editor). When capitalization is wrong in a tag, this error appears.

An example is the tag "God". If the tag "God" is registered in the database, and "god" is added to the item, the exception will appear after saving the item. Is there something to be done about this?

There was a similar bug a while ago. What version of Omeka are you running?

We are running 2.2.2. Is this solved in later editions? We haven't updated for a while because everything is running very stable otherwise (with our custom themes and plugins)

Yep. Looks like the first one in this list from the release notes

I don't think that there are any changes that would affect your themes and plugins between those two release.

Thanks, the exception seems to be fixed. Everything seems to be still working fine as well.