Special variable with current Makefile name?

[Markus Dehmann]

Is there a special variable that contains the name of the current 
Makefile?

I need this because my Makefile calls itself, but the filename is 
"rules.mk", not Makefile.

So, for a recursive call I need to say:
$(MAKE) $(MFLAGS) -f rules.mk

But "rules.mk" I do not want to hardcode.  I might want to change the 
file name at some point.

Thanks!
Markus