I submitted my site about 4 months ago and my associate just told me that he submitted our site 2 weeks ago to DMOZ. I was hoping that this isn't considered spamming and get us blocked. Is this ok?
If it was to the same category then the later one will overwrite the earlier one. All that might happen is that if the editor reviews in date received order (and fewer and fewer do these days) you will be a little further back down the track than previously. If it was to a different category then one will be deleted in due course - 2 submissions won't get you blocked. Technically it could I guess but not in practice. We reserve that for the real pains in the butt.
Post the URL and the category paths submitted to if you want, indicating which of the categories is the right one and which the wrong one. Someone might have the time to get rid of the wrong one for you.