The "111" stuff is executed before all the G_ClientInvMove code, the "222" stuff afterwards.
See http://mattn.ninex.info/patches/G_InventoryToFloor_debug4.patch for my debug code.

]singleplayergame 2.2-dev just started
]will drop a smg from 1. soldier to floor now
G_InventoryToFloor ================ 111
G_ClientInvMove ent inventory:
Container: 0
Container: 1
.. item.t: 26, item.m: 27, item.a: 50, x: 0, y: 0
.... weapon: smg
.... ammo:   smg_ammo (50)
Container: 2
Container: 3
.. item.t: 27, item.m: 255, item.a: 0, x: 1, y: 0
.... weapon: smg_ammo
.. item.t: 50, item.m: 255, item.a: 0, x: 2, y: 0
.... weapon: knife
.. item.t: 10, item.m: 255, item.a: 0, x: 3, y: 0
.... weapon: fraggrenade
.. item.t: 10, item.m: 255, item.a: 0, x: 0, y: 1
.... weapon: fraggrenade
.. item.t: 12, item.m: 255, item.a: 0, x: 3, y: 1
.... weapon: smokegrenade
Container: 4
.. item.t: 50, item.m: 50, item.a: 0, x: 0, y: 0
.... weapon: knife
.... ammo:   knife (0)
.. item.t: 10, item.m: 10, item.a: 0, x: 1, y: 0
.... weapon: fraggrenade
.... ammo:   fraggrenade (0)
.. item.t: 10, item.m: 10, item.a: 0, x: 2, y: 0
.... weapon: fraggrenade
.... ammo:   fraggrenade (0)
Container: 5
.. item.t: 12, item.m: 12, item.a: 0, x: 0, y: 0
.... weapon: smokegrenade
.... ammo:   smokegrenade (0)
Container: 6
Container: 7
Container: 8
Container: 9
G_ClientInvMove floor inventory:
G_InventoryToFloor ================ 111
G_InventoryToFloor ================ 222
G_ClientInvMove ent inventory:
Container: 0
Container: 1
Container: 2
Container: 3
.. item.t: 27, item.m: 255, item.a: 0, x: 1, y: 0
.... weapon: smg_ammo
.. item.t: 50, item.m: 255, item.a: 0, x: 2, y: 0
.... weapon: knife
.. item.t: 10, item.m: 255, item.a: 0, x: 3, y: 0
.... weapon: fraggrenade
.. item.t: 10, item.m: 255, item.a: 0, x: 0, y: 1
.... weapon: fraggrenade
.. item.t: 12, item.m: 255, item.a: 0, x: 3, y: 1
.... weapon: smokegrenade
Container: 4
.. item.t: 50, item.m: 50, item.a: 0, x: 0, y: 0
.... weapon: knife
.... ammo:   knife (0)
.. item.t: 10, item.m: 10, item.a: 0, x: 1, y: 0
.... weapon: fraggrenade
.... ammo:   fraggrenade (0)
.. item.t: 10, item.m: 10, item.a: 0, x: 2, y: 0
.... weapon: fraggrenade
.... ammo:   fraggrenade (0)
Container: 5
.. item.t: 12, item.m: 12, item.a: 0, x: 0, y: 0
.... weapon: smokegrenade
.... ammo:   smokegrenade (0)
Container: 6
Container: 7
.. item.t: 26, item.m: 27, item.a: 50, x: 3, y: 2
.... weapon: smg
.... ammo:   smg_ammo (50)
Container: 8
Container: 9
G_ClientInvMove floor inventory:
Container: 0
Container: 1
Container: 2
Container: 3
Container: 4
Container: 5
Container: 6
Container: 7
.. item.t: 26, item.m: 27, item.a: 50, x: 3, y: 2
.... weapon: smg
.... ammo:   smg_ammo (50)
Container: 8
Container: 9
G_InventoryToFloor ================ 222
]playing around now ..... let's test  this floor :)
G_InventoryToFloor ================ 111
G_ClientInvMove ent inventory:
Container: 0
Container: 1
Container: 2
Container: 3
.. item.t: 27, item.m: 255, item.a: 0, x: 1, y: 0
.... weapon: smg_ammo
.. item.t: 50, item.m: 255, item.a: 0, x: 2, y: 0
.... weapon: knife
.. item.t: 10, item.m: 255, item.a: 0, x: 3, y: 0
.... weapon: fraggrenade
.. item.t: 10, item.m: 255, item.a: 0, x: 0, y: 1
.... weapon: fraggrenade
.. item.t: 12, item.m: 255, item.a: 0, x: 3, y: 1
.... weapon: smokegrenade
Container: 4
.. item.t: 50, item.m: 50, item.a: 0, x: 0, y: 0
.... weapon: knife
.... ammo:   knife (0)
.. item.t: 10, item.m: 10, item.a: 0, x: 1, y: 0
.... weapon: fraggrenade
.... ammo:   fraggrenade (0)
.. item.t: 10, item.m: 10, item.a: 0, x: 2, y: 0
.... weapon: fraggrenade
.... ammo:   fraggrenade (0)
Container: 5
.. item.t: 12, item.m: 12, item.a: 0, x: 0, y: 0
.... weapon: smokegrenade
.... ammo:   smokegrenade (0)
Container: 6
Container: 7
.. item.t: 26, item.m: 27, item.a: 50, x: 3, y: 2
.... weapon: smg
.... ammo:   smg_ammo (50)
Container: 8
Container: 9
G_ClientInvMove floor inventory:
Container: 0
Container: 1
Container: 2
Container: 3
Container: 4
Container: 5
Container: 6
Container: 7
.. item.t: 26, item.m: 27, item.a: 50, x: 3, y: 2
.... weapon: smg
.... ammo:   smg_ammo (50)
Container: 8
Container: 9
G_InventoryToFloor ================ 111
G_InventoryToFloor ================ 222
G_ClientInvMove ent inventory:
Container: 0
Container: 1
Container: 2
Container: 3
.. item.t: 27, item.m: 255, item.a: 0, x: 1, y: 0
.... weapon: smg_ammo
.. item.t: 50, item.m: 255, item.a: 0, x: 2, y: 0
.... weapon: knife
.. item.t: 10, item.m: 255, item.a: 0, x: 3, y: 0
.... weapon: fraggrenade
.. item.t: 10, item.m: 255, item.a: 0, x: 0, y: 1
.... weapon: fraggrenade
.. item.t: 12, item.m: 255, item.a: 0, x: 3, y: 1
.... weapon: smokegrenade
Container: 4
.. item.t: 50, item.m: 50, item.a: 0, x: 0, y: 0
.... weapon: knife
.... ammo:   knife (0)
.. item.t: 10, item.m: 10, item.a: 0, x: 1, y: 0
.... weapon: fraggrenade
.... ammo:   fraggrenade (0)
.. item.t: 10, item.m: 10, item.a: 0, x: 2, y: 0
.... weapon: fraggrenade
.... ammo:   fraggrenade (0)
Container: 5
.. item.t: 12, item.m: 12, item.a: 0, x: 0, y: 0
.... weapon: smokegrenade
.... ammo:   smokegrenade (0)
Container: 6
Container: 7
.. item.t: 26, item.m: 27, item.a: 50, x: 4, y: 2
.... weapon: smg
.... ammo:   smg_ammo (50)
Container: 8
Container: 9
G_ClientInvMove floor inventory:
Container: 0
Container: 1
Container: 2
Container: 3
Container: 4
Container: 5
Container: 6
Container: 7
.. item.t: 26, item.m: 27, item.a: 50, x: 4, y: 2
.... weapon: smg
.... ammo:   smg_ammo (50)
Container: 8
Container: 9
G_InventoryToFloor ================ 222
InvAdd: message ignored... LE 30 not found
InvAdd: ignoring:
Item: smg
... name          -> Schwere Maschinenpistole
... type          -> pistol
... category      -> 50
... weapon        -> 1
... holdtwohanded -> 0
... firetwohanded -> 1
... twohanded     -> 0
... thrown        -> 0
... usable for weapon (if type is ammo):

]i dropped the smg and then tried to movbe it just one square to the right ... an armour (light) just appeared onscreen (inthe first square of the floor)