[thetwistedpanda]

Try using the 1.5 snapshot branch instead; 1.6 still has experimental changes. And I'll just leave this here, I was bored.

Spoiler

PHP Code:

public Action:CS_OnCSWeaponDrop(client, weapon)
{
    if(!IsValidEdict(weapon) || !IsClientInGame(client) || !IsPlayerAlive(client))
        return Plugin_Continue;

    decl String:sWeapon[32];
    GetEdictClassname(weapon, sWeapon, sizeof(sWeapon));
    if(!StrEqual(sWeapon, "weapon_c4"))
        return Plugin_Continue;
        
    new Handle:hPack = INVALID_HANDLE;
    CreateDataTimer(0.1, Timer_DropBomb, hPack);
    WritePackCell(hPack, GetClientUserId(client));
    WritePackCell(hPack, EntIndexToEntRef(weapon));

    return Plugin_Continue;
}

public Action:Timer_DropBomb(Handle:timer, Handle:pack)
{
    ResetPack(pack);
    new client = GetClientOfUserId(ReadPackCell(pack));        
    new entity = EntRefToEntIndex(ReadPackCell(pack));
    if(entity != INVALID_ENT_REFERENCE)
        AcceptEntityInput(entity, "Kill");
        
    if(client && IsPlayerAlive(client) && GetPlayerWeaponSlot(client, CS_SLOT_C4) == -1)    
        GivePlayerItem(client, "weapon_c4");
}