diff --git a/pypiserver/core.py b/pypiserver/core.py
index bef2ab3..7d8dc64 100755
--- a/pypiserver/core.py
+++ b/pypiserver/core.py
@@ -222,7 +222,8 @@ The following additional options can be specified with -U:
     the directory which contains the latest version of the package to
     be updated.
 
-
+  -u
+    allow updating to unstable version (alpha, beta, rc, dev versions)
 
 Visit http://pypi.python.org/pypi/pypiserver for more information.
 """
@@ -240,9 +241,10 @@ def main(argv=None):
     server = None
     update_dry_run = True
     update_directory = None
+    update_stable_only = True
 
     try:
-        opts, roots = getopt.getopt(argv[1:], "i:p:r:d:Uxh", ["interface=", "port=", "root=", "server=", "disable-fallback", "version", "help"])
+        opts, roots = getopt.getopt(argv[1:], "i:p:r:d:Uuxh", ["interface=", "port=", "root=", "server=", "disable-fallback", "version", "help"])
     except getopt.GetoptError, err:
         sys.exit("usage error: %s" % (err,))
 
@@ -266,6 +268,8 @@ def main(argv=None):
             command = "update"
         elif k == "-x":
             update_dry_run = False
+        elif k == "-u":
+            update_stable_only = False
         elif k == "-d":
             update_directory = v
         elif k in ("-h", "--help"):
@@ -288,7 +292,7 @@ def main(argv=None):
 
     if command == "update":
         from pypiserver import manage
-        manage.update(packages, update_directory, update_dry_run)
+        manage.update(packages, update_directory, update_dry_run, stable_only=update_stable_only)
         return
 
     server = server or "auto"
diff --git a/pypiserver/manage.py b/pypiserver/manage.py
index 813744c..c8c37ef 100644
--- a/pypiserver/manage.py
+++ b/pypiserver/manage.py
@@ -10,7 +10,24 @@ class pkgfile(object):
         self.version_info = pkg_resources.parse_version(self.version)
 
 
-def find_updates(pkgset):
+def is_stable_version(pversion):
+    for x in pversion:
+        if x.startswith("*final"):
+            return True
+        if x.startswith("*"):
+            return False
+    return False
+
+
+def filter_stable_releases(releases):
+    res = []
+    for pversion, version in releases:
+        if is_stable_version(pversion):
+            res.append((pversion, version))
+    return res
+
+
+def find_updates(pkgset, stable_only=True):
     no_releases = set()
 
     def write(s):
@@ -38,6 +55,9 @@ def find_updates(pkgset):
         releases = pypi.package_releases(pkgname)
 
         releases = [(pkg_resources.parse_version(x), x) for x in releases]
+        if stable_only:
+            releases = filter_stable_releases(releases)
+
         status = "."
         if releases:
             m = max(releases)
@@ -61,8 +81,8 @@ def find_updates(pkgset):
     return need_update
 
 
-def update(pkgset, destdir=None, dry_run=False):
-    need_update = find_updates(pkgset)
+def update(pkgset, destdir=None, dry_run=False, stable_only=True):
+    need_update = find_updates(pkgset, stable_only=stable_only)
     for x in need_update:
         print "# update", x.pkgname, "from", x.version, "to", x.latest_version