In the last few days, I have been preparing for the Advanced Developer Certification by going page by page through the recommended Salesforce Developers Guide. I was shocked when I received an error trying to save a sample page using the code supplied in the online guide (page 39). The sample page involved setting the tab order for fields in a form and the code referenced an attribute named TabIndex. When I attempted to save the sample page, I got the following error:
Unsupported attribute tabIndex in <apex:inputField> in myPage at line 5 column 56
In my experience so far, Salesforce has been excellent about keeping their docs up to date, but I am afraid this one may have slipped through the cracks. After doing a search through some forums, I discovered that the tabIndex attribute was replaced with a new attribute named tabOrderHInt in Winter 12. So, any code created since then (which is about a year at this point), will not work using the code example supplied in their online Developers Guide.
saramorgan.net 
thank . helping me