extrn question

Hey there.

I've got a question about extrn. Why do I seem to have to use:
extrn myFunc

rather than:
extrn 'myFunc' as myFunc:dword

When I'm combining two FASM-generated .obj files? I must extern all other functions that seem to come from .a libraries with the 2nd convention, and those that come from .obj files with 1st convention? Is there a way to change that?

Btw. I'm compiling with format MS COFF.

@EDIT

Actually, it does work, but I must call the function this way:
call exportedFunc

rather than this:
call [exportedFunc]

Well, I guess it's mean to be this way. Though, if anybody knows a way to force the call to include [ ], I'd appreciate it.

@EDIT2

Same goes for FASM-generated .a libs. Consider this example:

Code:

format MS COFF
extrn '__imp__printf' as printf:dword

section '.text' code
customFunc:
push dbg
call [printf]
add esp,4
ret

Then, I generate an .obj file by:
FASM customFunc.asm customFunc.obj

Then, I generate an .a file:
ar rcs libcustomfunc.a customFunc.obj

Then, I must do this to make it work:

Code:

format MS COFF
extrn 'customFunc' as customFunc:dword
section '.text' code
_start:
call customFunc
ret

Why is that? Why do I have to call printf by using the [ ], and I mustn't use them with my own function taken from shared library?

@nEDIT

Okay, I read this topic:
http://board.flatassembler.net/topic.php?p=108519

And now I kinda understand.. But is there any way for me to declare extern printf and call it without the brackets?
Like:
extrn '__imp__printf' as printf:dword
; ...
call printf

?

Cheers.