changing list types is not noticed?

[tomheady]

This:

1. four 
1. five 
1. six 

* one 
* two   
* three 

becomes an ordered list with six items.

this:

* one 
* two   
* three 

1. four 
1. five 
1. six 

becomes an unordered list with six items.

this:

1. four 
1. five 
1. six 

some text in between

* one 
* two   
* three 

becomes two lists with 3 items each, the first ordered and the second unordered.

I would expect two lists with three items each in all three cases. Is my expectation incorrect, or is this a bug?

[fletcher]

This is consistent with Markdown behavior, though it is under discussion on the Markdown list