What steps will reproduce the problem?
1. /* not entirely sure how to set up the scenario to cause the fail */
2. Hover over fubar item
3. receive error

What is the expected output? What do you see instead?
Error occurs when hovering over the Fubar item. The text on fubar appears to be correct however.

What version of the product are you using?
v1.1

Do you have an error log of what happened?
Date: 2009-02-23 12:22:40
ID: 1
Error occured in: Global
Count: 1
Message: ...rface\AddOns\FuBar_InstanceInfoFu\InstanceInfoFu.lua line 209:
   attempt to concatenate field '?' (a nil value)
Debug:
   [C]: ?
   ...rface\AddOns\FuBar_InstanceInfoFu\InstanceInfoFu.lua:209 ShowSavedInstanceInfo()
   ...rface\AddOns\FuBar_InstanceInfoFu\InstanceInfoFu.lua:189 ShowSavedInstances()
   ...rface\AddOns\FuBar_InstanceInfoFu\InstanceInfoFu.lua:171 OnUpdateFuBarTooltip()
   ...FuBar\libs\LibFuBarPlugin-3.0\LibFuBarPlugin-3.0.lua:634 runChildren()
   ...nterface\AddOns\FuBar\libs\Tablet-2.0\Tablet-2.0.lua:2370 children()
   ...nterface\AddOns\FuBar\libs\Tablet-2.0\Tablet-2.0.lua:2414 Open()
   ...nterface\AddOns\FuBar\libs\Tablet-2.0\Tablet-2.0.lua:2548
      ...nterface\AddOns\FuBar\libs\Tablet-2.0\Tablet-2.0.lua:2542
   ...FuBar\libs\LibFuBarPlugin-3.0\LibFuBarPlugin-3.0.lua:664
      ...FuBar\libs\LibFuBarPlugin-3.0\LibFuBarPlugin-3.0.lua:662

Please provide any additional information below.
It seems to only happen on realms where I have lower level characters, presumably since they wouldn't have any saved instances. I haven't seen this occur on a realm in which I have only 70+ chars.