I faced this problem when i was deploying to a farms that contains one Central administration (CA) server and to windows front end servers (WFE)

the problem was when trying to upgrade the wsp packages it didn’t execute the timer jobs in the other servers unless i force them by running the command "stsadm.exe -o execadmsvcjobs" on each front end server

The problem was that the timer jobs cached files was not the same on all the farm servers …

so i found out that topic

Which explains how to clear the caches across all servers by
1- Stop the OWSTIMER service on ALL of the MOSS servers in the farm.
2- On the Index server, navigate to %ALLUSERSPROFILE% \Application Data\Microsoft\SharePoint\Config\ and delete all the XML files from the directory.
3- Edit cache.ini and reset the number in the file to 1.
4- Start the OWSTIMER service on the Index server and wait for XML files to begin to reappear in the directory
5- After you see XML files appearing on the Index server, repeat steps 2, 3 & 4 on the query server(s), waiting for XML files to appear before moving to subsequent servers.
6- After the query servers have all been cleared, proceed to the WFE and Application servers in the farm, following steps 2, 3 & 4. for each server

of course you should make sure that the timer job service is started across all the servers

also notice that the timer job caches some dlls in the path c:\windows\assembly\temp

to know how to view that path please see this link

you can delete the cached dlls by closing the vs stopping the timer job and doing iisreset