Checking if your kit is complete...
Warning: the following files are missing in your kit:
	.#LetterTree.xs.1.7
	.#typemap.1.3
	LetterTree.bs
	LetterTree.c
	LetterTree.o
Please inform the author.
Note (probably harmless): No library found for -llettertree
Writing Makefile for Data::LetterTree
cp lib/Data/LetterTree.pm blib/lib/Data/LetterTree.pm
/home/cpanrun/build/5.6.1/bin/perl -I/home/cpanrun/build/5.6.1/lib/5.6.1/i686-linux-thread-multi -I/home/cpanrun/build/5.6.1/lib/5.6.1 /home/cpanrun/build/5.6.1/lib/5.6.1/ExtUtils/xsubpp  -typemap /home/cpanrun/build/5.6.1/lib/5.6.1/ExtUtils/typemap -typemap typemap LetterTree.xs > LetterTree.xsc && mv LetterTree.xsc LetterTree.c
Please specify prototyping behavior for LetterTree.xs (see perlxs manual)
gcc -c  -DUSE_REENTRANT_API -D_GNU_SOURCE -D_REENTRANT -fno-strict-aliasing -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -O2   -DVERSION=\"0.1\" -DXS_VERSION=\"0.1\" -fpic -I/home/cpanrun/build/5.6.1/lib/5.6.1/i686-linux-thread-multi/CORE  LetterTree.c
LetterTree.xs:7: lettertree.h: No such file or directory
make: *** [LetterTree.o] Error 1