Originally Posted by Sherrera
The exchange version is 6.5.7951.61, the BES which is on a seprate server is 6.5.6944.0.
So it sounds like you haven't gone to Exch SP2 on the BES. Assuming your Exch is at SP2 (which I am from the CDO version), you need to put Exch SP2 on the BES and the CDO.dll will be updated. It's always best practise to patch/upgrade the BES as soon as you do it on the Exchange server (apart from times like now when MS release an Exch update but RIM won't validate it!).
Get your BES onto Exch SP2 and you should find all is good. If it's not you might need to then apply the Exchange security patch but I am still running fine with a mismatch and won't patch till the man from RIM he say yes.