Well I'd say it comes down to two factors: How much your current job means to you and whether or not you think you have any chance at making some good progress with this app.

If you really don't think you're qualified and don't want to take a chance, play it safe and simply say "I don't think I'm ready for this." Else,why not? Worst case is the thing is a huge disaster and you can either go on with your job or get sick of the place and leave for better money.

I guarentee, though, if you take the job it will teach you some things about how much you really do and don't know, and that's valuable. About a year ago I was in a similiar situation stuck developing a complex reporting system in (ack) ASP. I managed to get a good deal done, but my planning and VB skills just weren't up to the task (that and the fact that they kept adding things on and on... went from one page to ~20 in around a month)

Anyhow, I got sick of the place (I was working part-time for crappy money) and started working contract. I'm much happier where I am now than where I would have been if I was still working the other job. I also learned about the importance of design and planning, planning, planning before anything complex... also learned about getting people to sign off on projects before they start so they don't get out of control ("Ohh.. that was easy. Let's make it do this and this too!")

Anyhow, if you do accept the project and it is a success (always an outside chance) you can then leverage that for a raise... knowing the plumbing of the system can be job security for you.

Best of luck

--pizza

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