switch subtree to different remote branch

Consider this part of a repos开发者_运维技巧itory of mine:

/
 myproject
 django -> django/master (django/django @github)
 ... other dependencies

django is a subtree that I merged following this howto: How to use the subtree merge strategy

Now I found out that another dependency is incompatible with the current master of django and I want to switch to django/1.1.x for that reason. How do I do this?

Thanks in advance.

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A submodule merely points at a commit. Check out the proper commit, and add it to the parent module, and commit in the parent.