Currently using AutoCAD 2008, I have for some time enjoyed the ability to enter the mtext editor by double-clicking on the text itself, but after some recent system modifications I find that double-clicking only brings up the properties palette.  I've tried to find the solution in AutoCAD help, and looked for threads on this subject on this site, but to no avail.  I've already tried changing values for DBLCLKEDIT and PICKFIRST variables, but that didn't help, either.  Has anyone on this forum overcome this problem?  Any help would be appreciated.
CKHodges

right click and .... Mtext edit ...

Thanks, Apeiron. 
 
Actually, I already knew that way to do it, but wanted to restore the 'double-click'-ability that I had previously enjoyed.  Last night I was able to find it in Acad help. 
 
For those interested, you can go into
 
Tools >  Customize > Interface
 
and in the Customizations window, under Double Click Actions, you can assign an object-dependent action to any double click function (i.e. you can tell AutoCAD what action to take when you double click on an object, based on what kind of object it is.)  In my case, I just changed the action for double clicking on an mtext object to be opening the mtext editor, rather than opening the properties palette.