A jolly chap checking articles in paper packing? (5)
I believe the answer is:
armed
'packing?' is the definition.
(both can mean carrying a weapon)
'a jolly chap' is the wordplay.
'jolly' becomes 'RM' (jolly can mean a Royal Marine).
'chap' becomes 'Ed' (short for Edward).
'a'+'rm'+'ed'='ARMED'
'checking articles in paper' is the link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for armed that I've seen before include "Prepared for attack" , "prepared to shoot?" , "Carrying a weapon" , "unlike the Venus of Milo" , "Like Mars" .)