How to change profile in DCM?

I started to use DCM when I was not that familiar with the product and its
capabilities.

So when I first started it up it asked for a logon and password and since
this was a newly provisioned test LPAR I just used QSECOFR (maybe I should
not have) and the password.

Now I know better and have had created a profile on the LPAR which provides
some admin functions but not the same as QSECOFR

But then I fire up DCM and use my new logon and password I now no longer
have access to the *SYSTEM certificate store. That is not surprising but I
cannot find any way to remove the persistent logon in my browser (Firefox)
so I can login as QSECOFR. I tried deleting cookies etc. and nothing
works. Everytime I fire up DCM on Firefox it automatically logs me on as
the new profile.

The only way I can get back to administering DCM on the LPAR is to use IE (
:-( ) which DCM asked me to logon and I used QSECOFR.

Is there something in IBMi I can use to delete my profile for DCM so it
will ask me to logon again in Firefox?

Thanks