More reader mail:

“I am a recent graduate. I just made a huge mistake in a salary negotiation and am wondering if there is something I can do to fix it. This was the first interview and I was not prepared to discuss salary, as I know it is a huge no-no. Unfortunately, the interviewer’s second question was, “What is your salary expectation?” Instead of answering with the question, “Well, what is the range for the job?” I said, “Between $37 and 45,000, but it is negotiable.” I said this before I even knew what my duties would be. I don’t know what I was thinking! That is well below the average for the position in my area; the range is $50,000 to $60,000 with a median of $55,000. Do I have to stick with what I said at the job offer, or can I begin negotiating at a higher level? The salary that I had given was for a position from another company.”

Well, at some level I feel like it’s too late and you’re stuck, but on the other hand, it’s sure a good test for your future employer for you to have a frank discussion with them about the situation and explain what happened.
In general, if you get a question in an interview that you’re not prepared to answer, I would encourage you to say just that: “Ah, well, I haven’t really thought about a salary: at this point I’m still trying to see if I’ll be a good fit for your company and at what level I’ll be able to contribute” would be a good way to defer.
I’ll also point out that until you were to get an offer in writing from the second company, the number they threw out about a starting salary isn’t worth much of anything, and would certainly be a dangerous basis for negotiation. Remember, if you tell your new employer that you’re not happy with the salary, they could think you’re greedy and invite you to join the other company, who could then explain that they no longer have a position for you.
Am I offering up conflicting advice? Yep. Its a tricky situation you’re in and I would encourage you to tread carefully. Decide which would be worse: having a job and gaining industry experience at a salary lower than you believe you’re worth, or ending up with no job and you’re back in the market?
Good luck and let us know what you decide to do and how it goes…