Welcome to WebmasterWorld Guest from 184.108.40.206
As we already used a query attached to the URL to provide tracking this caused the error.
Anyone else seen the query string added to their Dest URL? How long has this been going on?
I have my own strings attached too, and can't reproduce what you reported. However Google is known for A/B-Testing certain features, so maybe you are part of a test group.
If it breaks your system, you should contact them.