Install ESE on top of WSE.  That works fine.  I don't recall off the top of
my head if you can then uninstall WSE without uninstalling ESE - if they
show up in Add/Remove programs independantly, then you probably can.
Otherwise, you'll need both the ESE and WSE fixpacks to upgrade.

Note that if you've already applied a fixpack, you'll need that level of
ESE.  You can download the ESE fixpack for that level and use it to install
ESE, and then install the license from your ESE CD.

Hope that helps,

Go to the DB2 Universal Database for Linux, Unix, and Windows Support
site at:

http://www-306.ibm.com/software/data/db2/udb/support/

and do a search for "Changing DB2 Product Editions"

You should come up with two recent articles (one for Unix, the other
for Windows) that describe exactly how to do this.

Please reply back and let all of us that follow this group know your
results and how well the process works.

Thanks.