more infos after a night of test.
On my treo 680 the 4th button arise the frequent-app-menu and so it is not available.
I didn't find where to change the default configuration for the apt-menu.
However i've found a very-hard-workaround.
Because the apt-menu:Getcoord is a DA you can install the DA launcher manager.
Unfortunately this ca be activated only using the "/" pen stroke that is not available on the treo keyboard; so I Installed Graffiti anywhere just to do it.
So, in any application (I need to integrate in APT) I pres the 1st button (default in GA) and I did the "/" stroke using the pen; doing this gesture the list of all DA appears and I can select GetCoord, then I press the button and the GetCoord popup window show me all information that I can type in the ad hoc field in APT.
As said a very-hard-workaround.
I hope the someone else will be able to find a much manageable solution.
By the way
I can confirm that on treo 680 the PhonOFF temporized function works very well, today I'll test a temporized function to align SNTP time using SNTP (a free application you can easiliy find on freewarepalm),
So I can definitively fix this stupid problem (Treo's clock is a little too fast).