What steps will reproduce the problem?
1. Joining an arena.
2.
3.

What is the expected output? What do you see instead?
I do not see the arena frames, instead it gives me an error code.

What version of the product are you using?

v 2.0.16-beta
Do you have an error log of what happened?
Yes, I'll post it below.

Please provide any additional information below.
Date: 2011-12-12 23:36:19
ID: 1
Error occured in: Global
Count: 1
Message: ..\AddOns\Gladius\modules\auras.lua line 125:
   attempt to index field '?' (a nil value)
Debug:
   [C]: ?
   Gladius\modules\auras.lua:125 UNIT_AURA()
   Gladius\modules\auras.lua:220 CreateFrame()
   Gladius\modules\auras.lua:229 ?()
   Gladius\Gladius.lua:40 Call()
   Gladius\Gladius.lua:518 UpdateUnit()
   Gladius\Gladius.lua:364 JoinedArena()
   Gladius\Gladius.lua:333 ?()
   Gladius\Gladius.lua:22
      Gladius\Gladius.lua:13
AddOns:
  Swatter, v5.12.5198 (QuirkyKiwi)
  Arh, v0.91
  Auctionator, v3.0.0
  Bartender4, v4.4.20.1
  BattlegroundTargets, v40300-1
  BaudBag, v4.3.0
  ButtonFacade, v4.2.375
  DBMCore, v
  DebuffFilter, v3.21
  DoomCooldownPulse, v
  ErrorMonster, v3
  Gladius, vv2.0.16-beta
  Masque, v4.2.375
  MasqueRenaitre, vv4.3
  OmniCC, v4.3.0
  Prat30, v3.4.25    
  Prat30Libraries, v
  Quartz, v3.0.8
  Recount, v
  SexyMap, v
  ShadowedUnitFrames, vv3.4.4
  TidyPlates, v6.4.8.5 (R364)
  TidyPlatesGraphite, v
  TidyPlatesGrey, v
  TidyPlatesNeon, v
  TidyPlatesQuatre, v
  TidyPlatesHub, v
  TidyPlatesWidgets, v
  WowDings, v1.1
  BlizRuntimeLib_enUS v4.3.0.40300 <us>
  (ck=298)