Alan, here's another instance of the problem:

> The steps were:
> 1. Edited a C++ header file in a buffer.
The file is attached (libxmlparser.h).
I've had it open in a buffer for a while and have edited it successfully
(without the indentation problem) within the current emacs session.
I just switched to it from another buffer.

> 4. Added a #include to the top of the buffer.
4.1 I added a newline on line 8.
4.2 I then added another #include (pasted using C-y): #include
<libxml/xpath.h>
4.3 I then added another newline under the new #include.

> 5. Indentation for all code blocks following the include, when using
Tested line 14 (of the updated file) with a [TAB] and noticed the
forward declaration got moved to column 0.

When I undo all changes (steps 4.3 to 4.1), indentation is OK (remains
at respective column). When I repeat the steps, indentation gets moved
to column 0.

Best!
Piotr