diff --git a/pisi/build.py b/pisi/build.py
index 706e7e04..5782e0ae 100644
--- a/pisi/build.py
+++ b/pisi/build.py
@@ -91,7 +91,7 @@ class PisiBuild:
         # check if source already cached
         destpath = fetch.filedest + "/" + fetch.filename
         if os.access(destpath, os.R_OK):
-            if util.md5_file(destpath) == self.spec.source.archiveMD5:
+            if util.sha1_file(destpath) == self.spec.source.archiveSHA1:
                 ui.info('%s [cached]\n' % self.spec.source.archiveName)
                 return
 
diff --git a/pisi/files.py b/pisi/files.py
index a7d0b4ef..706bdd55 100644
--- a/pisi/files.py
+++ b/pisi/files.py
@@ -7,7 +7,7 @@ class FileInfo:
         self.path = getNodeText(getNode(node, "Path"))
         self.type = getNodeText(getNode(node, "Type"))
         self.size = int(getNodeText(getNode(node, "Size")))
-        self.md5Sum = getNodeText(getNode(node, "MD5Sum"))
+        self.hash = getNodeText(getNode(node, "Hash"))
 
     def elt(self, dom):
         ## FIXME: looking for a better way to do it
@@ -19,12 +19,12 @@ class FileInfo:
         typeElt.appendChild(dom.createTextNode(type))
         sizeElt = dom.createElement("Size")
         sizeElt.appendChild(dom.createTextNode(str(size)))
-        md5Elt = dom.createElement("MD5Sum")
-        md5Elt.appendChild(dom.createTextNode(md5sum))
+        hashElt = dom.createElement("Hash")
+        hashElt.appendChild(dom.createTextNode(hash))
         elt.appendChild(pathElt)
         elt.appendChild(typeElt)
         elt.appendChild(sizeElt)
-        elt.appendChild(md5Elt)
+        elt.appendChild(hashElt)
         return elt
 
 class Files(XmlFile):
diff --git a/pisi/specfile.py b/pisi/specfile.py
index ac25175d..b654108b 100644
--- a/pisi/specfile.py
+++ b/pisi/specfile.py
@@ -63,7 +63,7 @@ class SpecFile(XmlFile):
         self.source.archiveUri = getNodeText(archiveNode).strip()
 	self.source.archiveName = basename(self.source.archiveUri)
 	self.source.archiveType = getNodeAttribute(archiveNode, "archType")
-	self.source.archiveMD5 = getNodeAttribute(archiveNode, "md5sum")
+	self.source.archiveSHA1 = getNodeAttribute(archiveNode, "sha1sum")
         patchElts = self.getChildElts("Source/Patches")
 	if patchElts:
 	    self.source.patches = [PatchInfo(p) for p in patchElts]
diff --git a/pisi/util.py b/pisi/util.py
index cd700f8e..91723112 100644
--- a/pisi/util.py
+++ b/pisi/util.py
@@ -4,7 +4,7 @@
 
 import os
 import sys
-import md5
+import sha
 import shutil
 import statvfs
 
@@ -67,15 +67,15 @@ def get_file_hashes(top):
     for root, dirs, files in os.walk(top, topdown=False):
 	for file in files:
 	    f = os.path.join(root, file)
-	    yield (f, md5_file(f))
+	    yield (f, sha1_file(f))
 
 def copy_dir(src, dest):
     """copy source dir to destination dir recursively"""
     raise UtilError("not implemented")
 
-def md5_file(filename):
-    """calculate md5 hash of filename"""
-    m = md5.new()
+def sha1_file(filename):
+    """calculate sha1 hash of filename"""
+    m = sha.new()
     f = file(filename, 'rb')
     for l in f:
         m.update(l)
diff --git a/samples/popt/popt.pspec b/samples/popt/popt.pspec
index de4ce80a..03f29f07 100644
--- a/samples/popt/popt.pspec
+++ b/samples/popt/popt.pspec
@@ -13,7 +13,7 @@
       <Email>hotmail@redhat.com</Email>
     </Packager>
     <License>As-Is</License>
-    <Archive archType="targz" md5sum="5988e7aeb0ae4dac8d83561265984cc9">
+    <Archive archType="targz" sha1sum="66f3c77b87a160951b180447f4a6dce68ad2f71b">
       ftp://ftp.rpm.org/pub/rpm/dist/rpm-4.1.x/popt-1.7.tar.gz
     </Archive>
     <Patches>
diff --git a/tests/archivetests.py b/tests/archivetests.py
index 14f639c2..617cb8b9 100644
--- a/tests/archivetests.py
+++ b/tests/archivetests.py
@@ -34,8 +34,8 @@ class ArchiveFileTestCase(unittest.TestCase):
 	assert pathexists(testfile)
 	
 	# check file integrity
-	self.assertEqual(util.md5_file(testfile),
-			 "171545adab7b51ebf6ec5575d3000a95")
+	self.assertEqual(util.sha1_file(testfile),
+			 "5af9dd7d754f788cf511c57ce0af3d555fed009d")
 
     def testUnpackZip(self):
 	ctx = context.Context("tests/sandbox/sandbox.pspec")
@@ -57,8 +57,8 @@ class ArchiveFileTestCase(unittest.TestCase):
 	assert pathexists(testfile)
 	
 	# check file integrity
-	self.assertEqual(util.md5_file(testfile),
-			 "1e0c3f1e4664ee8ca67caea8b6b12ea4")
+	self.assertEqual(util.sha1_file(testfile),
+			 "06d0ee5ba49eccae6bc20552d55b3ba5ad52995e")
 
 	# check for symbolic links
 	testfile = targetDir + "/sandbox/deneme/hed"
diff --git a/tests/fetchertests.py b/tests/fetchertests.py
index 03ae0ad0..a67f7102 100644
--- a/tests/fetchertests.py
+++ b/tests/fetchertests.py
@@ -16,8 +16,8 @@ class FetcherTestCase(unittest.TestCase):
 	self.fetch.fetch()
 	destpath = self.fetch.filedest + "/" + self.fetch.filename
 	if os.access(destpath, os.R_OK):
-            self.assertEqual(util.md5_file(destpath),
-			     self.ctx.spec.source.archiveMD5)
+            self.assertEqual(util.sha1_file(destpath),
+			     self.ctx.spec.source.archiveSHA1)
 
 
 suite = unittest.makeSuite(FetcherTestCase)
diff --git a/tests/sandbox/sandbox.pspec b/tests/sandbox/sandbox.pspec
index 5660d106..a0eb04e5 100644
--- a/tests/sandbox/sandbox.pspec
+++ b/tests/sandbox/sandbox.pspec
@@ -13,7 +13,7 @@
       <Email>meren@uludag.org.tr</Email>
     </Packager>
     <License>As-Is</License>
-    <Archive archType="zip" md5sum="2ac9dfd81c07a91019d628268fee6ce1">
+    <Archive archType="zip" sha1sum="b1e61fe4a840fbe624a01136e33343cdd1b0bf06">
         http://cekirdek.uludag.org.tr/~meren/sandbox.zip
     </Archive>
     <History>
diff --git a/tests/specfiletests.py b/tests/specfiletests.py
index f5a4d060..ca9d6b63 100644
--- a/tests/specfiletests.py
+++ b/tests/specfiletests.py
@@ -20,9 +20,9 @@ class SpecReadTestCase(unittest.TestCase):
 	self.assertEqual(self.spec.source.release,
 			 "3")
 
-    def testMD5Sum(self):
-	self.assertEqual(self.spec.source.archiveMD5,
-			    "5988e7aeb0ae4dac8d83561265984cc9")
+    def testSHA1Sum(self):
+	self.assertEqual(self.spec.source.archiveSHA1,
+			    "66f3c77b87a160951b180447f4a6dce68ad2f71b")
 
     def testLenPackages(self):
 	self.assertEqual(len(self.spec.packages), 1)