Try the porcelain filler 1st (see pic.)...called porc-a-filler
Then try porc-a-fix over that (see pic.2)...Hopefully that does the job.
Check out this website below for info. AOL Image Search results for "porcelain fix"
Or could try the stuff KISS suggested....lots of good products out there that will fill that hole.
Let us know how it goes...Mark
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