With Build No. 4.1.B.0.431/.587
I don't know if anyone has posted it yet. So, I am just sharing my experience.
You all know that in ICS we can't use lock screen and security lock at the same time. By using this mod we can use both at the same time like in gingerbread. I am not posting modded file as all the ROMs has different files. So, by this guide you can implement it in your ROM yourself.
Tested with NXT lock screen also
Make Backup first
Decompile you android.policy.jar and then, go to out\com\android\internal\policy\impl\ and open...
LockPatternKeyguardView.smali and search for this...
iput-boolean v1, p0, Lcom/android/internal/policy/impl/LockPatternKeyguardView;->mShowLockBeforeUnlock:Z
Note that there are two lines of the same code, you have to change only the first one [at line 157 or somewhere around], don't change the other one.
iput-boolean v2, p0, Lcom/android/internal/policy/impl/LockPatternKeyguardView;->mShowLockBeforeUnlock:Z
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