Maybe the mechanic's tool? I don't know if that is a weapon or not, but if it is an you don't have it then...
Speaking about the mechanic's tool... You know, I've been bothered by not finding a way to change weapons from those in the little round weapon selector except by going to a machine or store and activating them there. Does anyone know a way to get all your weapons "online" so to speak so that you can get whatever one you need on the fly while you are out in the field? That would be handy. A couple of times I encountered guys with broken down cars and though I did have the tool in the "rucksack", I could not immediately produce it because I had other things in the 4 slots available in the game and didn't know how to get something different on the spot. So if anyone knows how to do that please reply.
PS... I'm also one of those ol' retired guys who spends his nights playing games, and although I used to fix computers for a living, some of this software eludes me. I'd call the inventory system in this game "Bysantine" at best.
[Edited by JustSomeGuy, 12/14/2012 3:11:50 AM]
Until now, there is no way to do such thing. I've been searching for mods like this since the game launched but no luck. But, since some players got the missing Camera and Stones bug, probably someone will figure out how to replace those items or to assign weapons to the C4/Mines places in the weapon wheel. Good luck searching, if you find please post here!
About the missing weapon: try to use the new trainer option to unlock all items in the vending machine/shops and se if an exclamation point shows up.