binding-names of members of working-collection

Hi,
Working-collections contain binding to version-histories. But what is not
clear, is the binding-name of such bindings. 

To illustrate, take a collection hierarchy:
/coll/
     |
     +- /a
     |
     +- /b
     |
     +- /c

The binding-names in the version-controlled-collection "coll" would be "a",
"b" and "c".
Assume that the version-history of /coll/a is at URL /vh/vh20. Since the
version-history is a DAV resource, it can have the name "vh20". Similar
version-histories for /coll/b and /coll/c are at /vh/vh21 and /vh/22.

When we CHECKOUT "coll", we get the working-collection "/wr/wr123". 
What should the PROPFIND on /wr/wr123 return?
a) /wr/wr123/vh20 (binding-name is the 'name' of the version-history),
/wr/wr123/vh21 and /wr/wr123/vh22
OR
b) /wr/wr123/a (binding-name is still the same as the binding-name in the
version-controlled-collection), /wr/wr123/b and /wr/wr123/c

Certainly the latter is more convenient. However, is this specifically
mentioned in the spec?

Thanks,
Girish