After I tested my alfresco community 4.0.d installation for a while, I found that the tag management function and tag choice UI doesn't work. I got this exception when I try to select a tag to apply to a document:
I have investigated JIRA and found issue ALF-10150 and ALF-9810 is exact the same as what happened on my installation. But these two issues are marked as "Cannot Reproduce" and closed.
When I was playing with alfresco, I tried to add Chinese tag when I am editing tasks in the calendar and found that no tag is added and no error message (simply nothing happened). After that the error occurred. This may be a hint to reproduce the issue.
please raise a bug with as much detail as possible. Include the locale of the machine, OS and browser/client. Did you do this as a normal user or someone with admin rights? What was the exact tag you added?