I recently discovered that an old Chinese multiple-entry visa sticker had fallen off my old trusty passport. It left a big discolored "rectangle" on one page. This missing area was then partially filled in by a Japanese visa sticker and other stamps, but the anomaly is quite obvious - I'm shocked that the Japanese immigration officer didn't notice it. I travel constantly and never paid any attention to stamps and such. At any rate, I reported this to the Chinese consulate and they told me I should have made an effort to find it, and since it was issued and now missing, the Chinese authorities would consider my passport void next time I enter China (that is, if they take a look). My passport has another Chinese visa, and I hate to waste money on either another passport or another visa. Any comments or suggestions from experienced travellers?