I wouldnt say it is an Islamic idea, by the way, although they may have glommed that aspect of their belief from Eastern Christian thought on the issue at the time, and that would not be surprising.
I think this is where the Augustinian definitions, if you hold firmly to them, leave you with the nagging need for a place like limbo for unbaptized persons who die without having committed actual sin (ie infants, small children) ... because they are *stained* by Original Sin and therefore cannot enter into full communion with God. I think that you can get away from this, even with the Western perspective, by believing in some kind of extraordinary mercy for persons in this situation, such that they are in effect baptized by God's mercy, but I don't think that this idea has ever been formally taught by the Roman Catholics.