If you need to defragment your Exchange database at a computer without Exchange components, you will probably use this MS KB: 244525: How to run Eseutil on a computer without Exchange Server. I tried it when I was defragmenting Exchange 2003 database at a Windows Server 2008 R2 machine.
Eseutil was running fine, but after some time (when it used just over 2 GBs of RAM), I received an error described here: 273087: Error With Jcb.dll While Running Eseutil. Unfortunately, none of the methods described there were useful: when I pressed «Cancel» button, I received an «Operation terminated with error -2102 JET_errCallbackNotResolved, A callback function could not be found) after 1168.136 seconds.» error.
Eventually, I grabbed Process Monitor and found out that files described in Microsoft’s KB 244525 and in this thread «Re: JCB.DLL Not Found Error» weren’t enough – you need another one file: ntlsapi.dll. I copied it from a nearest Windows Server 2003 R2 SP2 box to a system where eseutil were working and everything went smoothly.