diff --git a/libretroshare/src/ft/ftdatamultiplex.cc b/libretroshare/src/ft/ftdatamultiplex.cc
index 315c7b6f4..6c36c4114 100644
--- a/libretroshare/src/ft/ftdatamultiplex.cc
+++ b/libretroshare/src/ft/ftdatamultiplex.cc
@@ -489,12 +489,12 @@ bool 	ftDataMultiplex::doWork()
 	return true;
 }
 
-bool ftDataMultiplex::recvSingleChunkCrc(const std::string& /*peerId*/, const std::string& hash,uint32_t chunk_number,const Sha1CheckSum& crc)
+bool ftDataMultiplex::recvSingleChunkCrc(const std::string& peerId, const std::string& hash,uint32_t chunk_number,const Sha1CheckSum& crc)
 {
 	RsStackMutex stack(dataMtx); /******* LOCK MUTEX ******/
 
 //#ifdef MPLEX_DEBUG
-	std::cerr << "ftDataMultiplex::recvSingleChunkCrc() Received crc of file " << hash << ", chunk " << chunk_number << ", crc=" << crc.toStdString() << std::endl;
+	std::cerr << "ftDataMultiplex::recvSingleChunkCrc() Received crc of file " << hash << ", from peer id " << peerId << ", chunk " << chunk_number << ", crc=" << crc.toStdString() << std::endl;
 //#endif
 
 	std::map<std::string, ftClient>::iterator it = mClients.find(hash);
@@ -757,7 +757,7 @@ bool ftDataMultiplex::computeAndSendCRC32Map(const std::string& peerId, const st
 
 	std::cerr << "Computing CRC32Map for file " << filename << ", hash=" << hash << ", size=" << filesize << std::endl;
 
-	FILE *fd = fopen(filename.c_str(),"r") ;
+	FILE *fd = RsDirUtil::rs_fopen(filename.c_str(),"rb") ;
 
 	if(fd == NULL)
 	{
@@ -899,7 +899,7 @@ bool ftDataMultiplex::handleRecvChunkCrcRequest(const std::string& peerId, const
 	std::cerr << "Computing Sha1 for chunk " << chunk_number<< " of file " << filename << ", hash=" << hash << ", size=" << filesize << std::endl;
 
 	unsigned char *buf = new unsigned char[ChunkMap::CHUNKMAP_FIXED_CHUNK_SIZE] ;
-	FILE *fd = fopen(filename.c_str(),"r") ;
+	FILE *fd = RsDirUtil::rs_fopen(filename.c_str(),"rb") ;
 
 	if(fd == NULL)
 	{
diff --git a/libretroshare/src/tests/util/sha1_test.cc b/libretroshare/src/tests/util/sha1_test.cc
index 811bd96eb..3af4c1829 100644
--- a/libretroshare/src/tests/util/sha1_test.cc
+++ b/libretroshare/src/tests/util/sha1_test.cc
@@ -47,7 +47,7 @@ int main(int argc,char *argv[])
 		return -1 ;
 	}
 
-	FILE *f = fopen(argv[1],"r") ;
+	FILE *f = RsDirUtil::rs_fopen(argv[1],"r") ;
 
 	if(f == NULL)
 	{
@@ -75,6 +75,19 @@ int main(int argc,char *argv[])
 	Sha1CheckSum H(hash) ;
 	std::cerr << "Hashed transformed: " << H.toStdString() << std::endl;
 
+	std::cerr << "Computing all chunk hashes:" << std::endl;
+
+	fseek(f,0,SEEK_SET) ;
+	int n=0 ;
+
+	while(len = fread(buf,1,SIZE,f))
+	{
+		Sha1CheckSum sum = RsDirUtil::sha1sum(buf,len) ;
+		std::cerr << "Chunk " << n << ": " << sum.toStdString() << std::endl;
+		n++;
+	}
+
+	fclose(f) ;
 	return 0 ;
 }