diff --git a/plugins/common/functions b/plugins/common/functions
index c495e8af1..d7d15dbc4 100755
--- a/plugins/common/functions
+++ b/plugins/common/functions
@@ -1057,7 +1057,7 @@ strip_inline_comments() {
 
 is_valid_hostname() {
   declare desc="return 0 if argument is a valid hostname; else return 1"
-  local hostname_string="$1"; local hostname_regex='^(([a-zA-Z\*](-?[a-zA-Z0-9])*)\.)*[a-zA-Z\*](-?[a-zA-Z0-9])+\.[a-zA-Z]{2,}$'
+  local hostname_string="$1"; local hostname_regex='^(([a-zA-Z0-9\*](-?[a-zA-Z0-9])*)\.)*[a-zA-Z\*](-?[a-zA-Z0-9])+\.[a-zA-Z]{2,}$'
   if [[ $hostname_string =~ $hostname_regex ]]; then
     return 0
   else
diff --git a/tests/unit/20_domains.bats b/tests/unit/20_domains.bats
index 497c82c69..cd52c6190 100644
--- a/tests/unit/20_domains.bats
+++ b/tests/unit/20_domains.bats
@@ -31,10 +31,14 @@ teardown() {
   echo "output: "$output
   echo "status: "$status
   assert_success
+  run dokku domains:add $TEST_APP 2.app.dokku.me
+  echo "output: "$output
+  echo "status: "$status
+  assert_success
 }
 
 @test "(domains) domains:add (multiple)" {
-  run dokku domains:add $TEST_APP www.test.app.dokku.me test.app.dokku.me
+  run dokku domains:add $TEST_APP 2.app.dokku.me www.test.app.dokku.me test.app.dokku.me
   echo "output: "$output
   echo "status: "$status
   assert_success