What is different about Diamond's PoS system then that makes it not have the usual problems so many other PoS coins have?
Is it a matter of which original type of PoS a given family of coins was cloned from?
For example the setting your clock forward less than two hours but maybe close to two hours, that one is apparently quite widespread?
You do not come across as knowledgeable about these problems so it is not clear that you have enough knowledge of them to actually even have seriously examined your code to be sure they do not apply to it?
For example the recent coin Axiom apparently has the problems, they are claiming to be looking into fixing them.
It is not clear whether the recent coin NINJA has them or not.
So far I have not come across any coherent explanation of which ancestries of coins have them or if maybe all of them do.
The problems are ancestral, dating back I don't know how far, inherited by many coins as they keep cloning each other.
-MarkM-
Currently unknown if it would be an issue for diamond or not.
Diamond is still more PoW than PoS, due to the number of blocks created being mostly PoW blocks.Diamond is a Hybrid using PoW & PoS to generate coins. (Edit For Popshot)
Easy test , would be to set the time on the PC with the reactor on it 1 hour fast and then observe the PoS difficulty when it staked , does the difficulty drop by ½ , and does it give the reactor increased # of stakes.
Peercoin has denied it being an issue and they are hybrid like diamond, but they have also not presented any test data to back up that claim.
But Diamond PoS difficulty is already low compared to others at 0.0359 , but the PoW difficulty is over 50.
PoS coins affected so far has been Hyperstake, Mint, & Zeit and all 3 have already fixed the timedrift issue.
If diamond code is affected, they only need to change in the Main.h file
static const int64 nMaxClockDrift = 2 * 60 * 60; // two hours To a shorter amount of time.
Hyperstake & Zeit went down to 1 minute
Mint went down to 30 seconds
Here is the original article by Presstab detailing the issue.
http://bitcoinist.net/interview-presstab-pos-vulnerabilities/ 
FYI:
So far no one has shown a Hybrid PoW /PoS coin being affected, only full PoS coins have shown the issue so far.
I still hold ALL DMD and staking 
