select arch with debuild

[Ste Pelux <pelux@tiscalinet.it>]

i converted sourcecode with dh_make , modified makefile and debian/* and 
succesfully compiled and buid package with debuild but can't  select arch.
in fact debuild (at some lines) says:
make[2]: Entering directory `/home/pelux/temp/mplayer-0.11.pre24/libmpeg2'
gcc -c -O4 -march=i686 -mcpu=i686 -pipe -ffast-math -DMPG12PLAY -I. 
-I../libvo -I.. -o decode.o decode.c

i want to comile everything in i386 to make the debian file available to 
everyone!
bye
Stefano