Blockquotes with code blocks using tabs

[Mark Henderson Linton]

I am working on my own filter that will do some text processing prior 
to Markdown. I want to make sure that I do not muck up any of the 
Markdown formatting, and so I have been playing with the "test suite." 
In particular, I am looking at "Blockquotes with code blocks.text" and 
I see that the test case only tests the case where the inner code block 
is indented with spaces, though the syntax implies that code blocks can 
be indented with tabs or spaces. If I create another test case where 
the code is indented with tabs, it is simply interpreted as paragraphs 
within the blockquote (using BBEdit or the Dingus).

Q: Do code blocks within blockquotes *have* to be indented with spaces?

- Mark