rosbag fix does not like rule produced by rosbag check

edit

I want to use rosbag fix to migrate some of the messages contained in one of my bag files since I converted one of my data types (asctec_hl/IMURaw) to a new one (asctec_msgs/IMUData).

I followed the Alternative Approach to Making Rules and did the following:

$ rosbag check in.bag -g myrules.bmr
The following migrations need to occur:
 * From: asctec_hl/IMURaw [f977ecf9dfe66d1c7d6ade693ec96195]
   To:   Unknown
    1 rules missing:
     * From: asctec_hl/IMURaw [f977ecf9dfe66d1c7d6ade693ec96195]
       To:   Unknown
The message type asctec_hl/IMURaw appears to have moved.  Please enter the type to migrate
it to.
>asctec_msgs/IMUData
Creating the migration rule for asctec_msgs/IMUData requires additional missing rules:

The necessary rule files have been written to: myrules.bmr

As explained in the docs I inspected the produced rule, modified it and set valid = True.

When trying to actually fix the bag with the produced rule I get:

$ rosbag fix in.bag out.bag myrules.bmr
Bag could not be migrated.  The following migrations could not be performed:
 * From: asctec_hl/IMURaw [f977ecf9dfe66d1c7d6ade693ec96195]
   To:   Unknown
    1 rules missing:
     * From: asctec_msgs/IMUData [4431bfb48b28d4830885ef905ffa3a5c]
       To:   Unknown
Try running 'rosbag check' to create the necessary rule files or run 'rosbag fix' with the
'--force' option.

Any suggestion about what might be wrong given that myrules.bmr specifies exactly the rule that rosbag fix claims is missing?

BTW: I am using fuerte (latest Ubuntu 12.04 binaries) and both of the packages in question (which belong to different stacks) are built using rosmake.

Submitted as ticket 4016