Through the Internet, there are many people who bumps into problems while using this IK Solver, especially when performing world rotation that seems not to affect the joints rigged with IK Spring Solver. This problem has been a plague since Maya 7.0 and no rectification is being done up till Maya 2009 (which I am using) to make it behave properly.
The only available fix to it, is to have the first joint of a series of joints bounded to an IK Spring Solver not to be parented to its whatever parent. That joint shall be parent constrained to whatever parent it supposed to be, instead of directly parented underneath them.
Note that IK Spring Solver will also break if you choose to parent the joints under a transform node and choose that transform node to perform the required parent-constraining. It is okay if you parent constrain the joints to whatever parents it supposed to be as described above, and group the joints in an empty transform node for clarity purposes.
I guess that is as much as I could explain. Please do drop a message if the problem persists, or my instructions being unclear.