Need help with makefiles

Hi all,

I have a problem with writing makefiles and I hope somebody can help  
me to solve it.
I have this code:

define gb_ConcatPo
$(foreach lang,$(filter-out en-US,$(gb_WITH_LANG)), $(shell cat  
$(gb_POLOCATION)/$(lang)/$(1) >> $(2) && printf "\n" >> $(2)))
endef

define gb_Transex3Merge
RESPONSEFILE=`$(gb_MKTEMP)`
$(call gb_ConcatPo,$(PO),@$${RESPONSEFILE})
$(call gb_SrsPartMergeTarget__command,$(1),$(2),$(3),@$${RESPONSEFILE})
rm -rf @$${RESPONSEFILE}
endef

It seems to work, but if I try to initialize the second parameter of  
gb_ConcatPo like this:

define gb_ConcatPo
echo "" > $(2)
$(foreach lang,$(filter-out en-US,$(gb_WITH_LANG)), $(shell cat  
$(gb_POLOCATION)/$(lang)/$(1) >> $(2) && printf "\n" >> $(2)))
endef

then the function will return with an empty file, as if foreach had no effect.


Thanks,
Zolnai Tamás