Can you set constraints for certain actions?
In blender the animations are separated in different actions.
I need different animations like walking and steering a car.
For steering the car I want to set a constraint to the hands that they move with the steering wheel, but for walking this constraint hinders.
How do you normally solve this?

i would have to experiment with this too but i think it could be done by animating the influence or on/off state of a constraint.

with blender 2.5x it should be quite straight forward since with the new animation system simply everything is animatable. in older versions the functionality could be more hidden but i am pretty sure that it is possible too.

Just tested it with the IK solver.
It is at the bottom of the constraint panel.
A shifter for the influence and button that
"Add influence keyframe to the constraint"

I need to make further tests, but it seems to do exactly what I was looking for.
I already tried it some time ago, but seems that I didn't use it in a proper way!
Thank you for your response!

EDIT: I still work with 2.49b

Additional question:

Does the pole target of an IK Solver work properly for anyone?

@ ventilator:
Just had a fifth or sixth look at your tutorial, and saw that you didn't use any pole target for the knees. Instead of that you used a second IK Solver for the upper leg bone. That works properly!
So, after such a long time, thank you for your blender animation tutorial, again! (Beside all the other great additions you gave to our Acknex experiences! )

pole targets are supposed to work better for knees than ik targets.

the reason i didn't use them is that they weren't available when i did the tutorial.

so maybe you can experiment with them again or ask at the blender forum. but if ik targets work fine for you then you can of course continue using them.

When I post my question on the blender forums, it happens that I can't find the thread with my post later, again.

The pole target twists some bones of the IK chain.
but, as you said, your way works for me, so I am satisfied.

Old thread, new question:

How can I import an animated file into blender?

I have a human model fully rigged and with many constraints, and I want to add several already animated devices(animated in MED and available only in the 3DGS .mdl format).

Probably it is easier to make the animations anew, but - who knows - maybe, someone of you know a fast and easy way?