Tables are not forbidden in general.
There is some information at the Mobipocket Developer Center at
http://www.mobipocket.com/dev/articl...ile=tables.htm
Quote:
"Table tags have to be used only when displaying tabular data and not like in Web page authoring for layout purposes. There is no exception to this rule."
If you consider the block quote as content of a cell, that means tabular data, and the table is not empty just for layout purposes, then I would say it is OK.
But:
Quote:
"Table parsing and display is very CPU intensive and is slow compared to any other HTML tag. Moreover, the Mobipocket reader can handle tables that are larger than the screen but the user experience becomes worse as the table size grows. You should therefore avoid large tables."
And:
"A table with a lot of text in one cell will not work well. If a single table cell does not fit into the screen, it will not be paginated and content will be lost."
So I would give it a try for just a block quote.
George