Description of problem:
I execute the command as follow on Bash 4.2.10 of Fedora 16:
$ [[ "abcd" =~ "a.*d" ]] && echo true
$ 

As Bash 3.2.25 of RHEL 5.4:
$ [[ "abcd" =~ "a.*d" ]] && echo true
true


Version-Release number of selected component (if applicable):
Bash 4.2.10

How reproducible:
[[ "abcd" =~ "a.*d" ]] && echo true

Steps to Reproduce:
1.
2.
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Actual results:
can echo "true"

Expected results:
doesn't echo "true"


Additional info: