diff --git a/deb/publish.go b/deb/publish.go
index 0083516f..7e1c5f9f 100644
--- a/deb/publish.go
+++ b/deb/publish.go
@@ -168,6 +168,9 @@ func NewPublishedRepo(storage, prefix, distribution string, architectures []stri
 		if distribution == "" || component == "" {
 			rootDistributions, rootComponents := walkUpTree(source, collectionFactory)
 			if distribution == "" {
+				for i := range rootDistributions {
+					rootDistributions[i] = strings.Replace(rootDistributions[i], "/", "-", -1)
+				}
 				discoveredDistributions = append(discoveredDistributions, rootDistributions...)
 			}
 			if component == "" {
@@ -227,6 +230,10 @@ func NewPublishedRepo(storage, prefix, distribution string, architectures []stri
 		}
 	}
 
+	if strings.Index(distribution, "/") != -1 {
+		return nil, fmt.Errorf("invalid distribution %s, '/' is not allowed", distribution)
+	}
+
 	result.Distribution = distribution
 
 	return result, nil
diff --git a/deb/publish_test.go b/deb/publish_test.go
index 56e1db95..60e3a226 100644
--- a/deb/publish_test.go
+++ b/deb/publish_test.go
@@ -167,6 +167,9 @@ func (s *PublishedRepoSuite) TestNewPublishedRepo(c *C) {
 
 	_, err := NewPublishedRepo("", ".", "a", nil, []string{"main", "main"}, []interface{}{s.snapshot, s.snapshot2}, s.factory)
 	c.Check(err, ErrorMatches, "duplicate component name: main")
+
+	_, err = NewPublishedRepo("", ".", "wheezy/updates", nil, []string{"main"}, []interface{}{s.snapshot}, s.factory)
+	c.Check(err, ErrorMatches, "invalid distribution wheezy/updates, '/' is not allowed")
 }
 
 func (s *PublishedRepoSuite) TestPrefixNormalization(c *C) {
@@ -267,6 +270,13 @@ func (s *PublishedRepoSuite) TestDistributionComponentGuessing(c *C) {
 	c.Check(repo.Distribution, Equals, "precise")
 	c.Check(repo.Components(), DeepEquals, []string{"contrib"})
 
+	s.localRepo.DefaultDistribution = "precise/updates"
+
+	repo, err = NewPublishedRepo("", "ppa", "", nil, []string{""}, []interface{}{s.localRepo}, s.factory)
+	c.Check(err, IsNil)
+	c.Check(repo.Distribution, Equals, "precise-updates")
+	c.Check(repo.Components(), DeepEquals, []string{"contrib"})
+
 	repo, err = NewPublishedRepo("", "ppa", "", nil, []string{"", "contrib"}, []interface{}{s.snapshot, s.snapshot2}, s.factory)
 	c.Check(err, IsNil)
 	c.Check(repo.Distribution, Equals, "squeeze")