Steps to reproduce:

1.Open a page with VE
2.Add a reference with a group name "first group"
3.Now Add a references list but under Use this group, type "first group one"
4.Apply changes.("there are no references with this group" will appear which is correct)
5.Now reopen the References list dialog again.
6.Just delete the "one" from "first group one" to make it "first group"
7.Apply changes

Observed Result:
Even this time it says "there are no references with this group" which is wrong.

Test Environment: http://en.wikipedia.beta.wmflabs.org/
Browser:FF 25
OS: MAC OS X 10. 8. 5

Version: unspecified
Severity: normal