Bugs are faults in the program. You said that you had checked them, and it was OK to include them in the product when it was released (to the public?) This was a statement, but because (presumably) English is not your native language, your coworker was checking whether you had meant to say this, or if you were asking him/her to agree that it was OK. Basically, he/she was saying, 'Well, if you include faults in the program when you release it, don't tell people that the reason you did that was because I said it was OK.'

I agree with Emily. Your original email is confusing and the recipient was trying to figure out what you meant. If I had received your email, I would have thought "Why does he think it's OK to include the bugs in the release? Is he saying that he fixed them and it's OK to include the fixes? Or is he saying that the bugs are unimportant and that it's OK to include them in the release without fixing them? OR is he asking me if it's OK to include the unfixed bugs in the release? I would certainly want more clarification from you about the meaning of your original email.

It certainly looks like a statement, and - without any further context - you would have no reason to presume it to be a question.

Oh, oops. I just thought of another way to read your original email. If someone submitted the bugs to you for review and you have the authority to approve the inclusion of the bugs in the release, then your sentence could have been written: As far as I am concerned, it is OK for these bugs to be included in the release. The confusion comes from two different meanings of "it's OK for me". 1) It is permissible for me to do X. This leads to the idea that you might be asking for permission i.e. ("is it OK for me to include the bugs?") 2) It is acceptable to me if X happens. In this case, your sentence could have been written "It is OK as far as I am concerned if (someone else) includes the bugs in the release."