Keyword search function on Safari not work iPhone 4

My iPhone 4 has 4.2.1 installed.
I can tap the search field, enter a keyword and safari will indeed report it found matches on the current safari webpage.
I then scroll down to the bottom of the search results to where it says Find keyword and I tap it.
The Next and Done buttons appear on the toolbar at the bottom, but when I tap the Next button, nothing happens and the screen stays exactly where it was before I tapped the Next button.
My understanding is that after I tap the Next button, the screen is supposed to scroll to the next matched keyword and that the keyword is supposed to be hilited in yellow. Even when I manually scroll down the screen after hitting Next, the matched keywords are not hilited in yellow.
Help!
MBP 17" 2.66ghz Mac OS X (10.6.4) iPhone 4, 4.2.1