diff --git a/lib/gitlab/client/merge_requests.rb b/lib/gitlab/client/merge_requests.rb
index bdfdb1270..7f33427c7 100644
--- a/lib/gitlab/client/merge_requests.rb
+++ b/lib/gitlab/client/merge_requests.rb
@@ -50,10 +50,7 @@ def merge_request(project, id)
     #
     # Accepts source_branch, target_branch, assignee_id, & title in params.
     def create_merge_request(project, params={})
-
-      raise("Attribute source_branch is required.") unless params.has_key?(:source_branch)
-      raise("Attribute target_branch is required.") unless params.has_key?(:target_branch)
-      raise("Attribute title is required.")         unless params.has_key?(:title)
+      check_attributes!(params, [:source_branch, :target_branch, :title])
 
       post("/projects/#{project}/merge_requests",
         :body => params
@@ -99,12 +96,22 @@ def update_merge_request(project, merge_id, params={})
     # Accepts note (And alias, comment)
     def comment_merge_request(project, merge_id, params={})
       params[:note] = params[:comment]     if params.has_key?(:comment)
-      raise("Attribute note is required.") unless params.has_key?(:note)
+      check_attributes!(params, [:note])
 
       post("/projects/#{project}/merge_request/#{merge_id}/comments",
         :body => params
       )
     end
 
+    private
+
+    def check_attributes!(options, attrs)
+      attrs.each do |attr|
+        unless options.has_key?(attr) || options.has_key?(attr.to_s)
+          raise Gitlab::Error::MissingAttributes.new("Missing '#{attr}' parameter")
+        end
+      end
+    end
+
   end
 end
diff --git a/lib/gitlab/error.rb b/lib/gitlab/error.rb
index daf48b919..2e0d4415e 100644
--- a/lib/gitlab/error.rb
+++ b/lib/gitlab/error.rb
@@ -3,6 +3,9 @@ module Error
     # Custom error class for rescuing from all Gitlab errors.
     class Error < StandardError; end
 
+    # Raise when attributes are missing.
+    class MissingAttributes < Error; end
+
     # Raised when API endpoint credentials not configured.
     class MissingCredentials < Error; end
 
diff --git a/spec/gitlab/client/merge_requests_spec.rb b/spec/gitlab/client/merge_requests_spec.rb
index 093e26bd6..64936074a 100644
--- a/spec/gitlab/client/merge_requests_spec.rb
+++ b/spec/gitlab/client/merge_requests_spec.rb
@@ -36,14 +36,35 @@
   describe ".create_merge_request" do
     before do
       stub_post("/projects/3/merge_requests", "create_merge_request")
-      @merge_request = Gitlab.create_merge_request(3,
-        :source_branch => 'api',
+    end
+
+    it "should fail if it doens't have a source_branch" do
+      expect { Gitlab.create_merge_request(3,
         :target_branch => 'master',
         :title         => 'New feature'
-      )
+      ) }.to raise_error Gitlab::Error::MissingAttributes
+    end
+
+    it "should fail if it doens't have a target_branch" do
+      expect { Gitlab.create_merge_request(3,
+        :source_branch => 'master',
+        :title         => 'New feature'
+      ) }.to raise_error Gitlab::Error::MissingAttributes
+    end
+
+    it "should fail if it doens't have a title" do
+      expect { Gitlab.create_merge_request(3,
+        :target_branch => 'master',
+        :source_branch => 'master'
+      ) }.to raise_error Gitlab::Error::MissingAttributes
     end
 
     it "should return information about a merge request" do
+      @merge_request = Gitlab.create_merge_request(3,
+        :source_branch => 'api',
+        :target_branch => 'master',
+        :title         => 'New feature'
+      )
       @merge_request.project_id.should == 3
       @merge_request.assignee.name.should == "Jack Smith"
       @merge_request.title.should == 'New feature'
@@ -70,12 +91,18 @@
   describe ".comment_merge_request" do
     before do
       stub_post("/projects/3/merge_request/2/comments", "comment_merge_request")
-      @merge_request = Gitlab.comment_merge_request(3, 2,
-        :note => 'Cool Merge Request!'
-      )
+    end
+
+    it "should fail if it doens't have a note" do
+      expect {
+        Gitlab.create_merge_request(3)
+      }.to raise_error Gitlab::Error::MissingAttributes
     end
 
     it "should return information about a merge request" do
+      @merge_request = Gitlab.comment_merge_request(3, 2,
+        :note => 'Cool Merge Request!'
+      )
       @merge_request.note.should == 'Cool Merge Request!'
       @merge_request.author.id == 1
     end