Index: hawk/public/dispatch.fcgi
===================================================================
--- hawk/public/dispatch.fcgi.orig
+++ hawk/public/dispatch.fcgi
@@ -23,6 +23,42 @@
 # we can pull rubygems from there
 $LOAD_PATH.unshift(File.dirname(__FILE__) + "/../vendor")
 
+# Workaround for bnc#579874 (ruby: String#unpack("V") does not work correctly on s390x)
+if [1].pack('V').unpack('V')[0] != 1
+  class String
+    alias_method :broken_unpack, :unpack
+    def unpack(spec)
+      # use regular unpack first...
+      unpacked = broken_unpack(spec)
+      if spec.include? 'V'
+        # ...then, if there's a 'V' anywhere, expand the spec
+        # (need this to handle numeric and '*' parts of spec)...
+        parts = spec.scan(/[0-9]+|[^0-9]/)
+        spec = ''
+        final = ''
+        parts.each_with_index do |x,i|
+          n = x.to_i
+          if n > 0
+            (n-1).times { spec += parts[i-1] }
+          else
+            spec += x
+            final = x unless x == '*'
+          end
+        end
+        # ...and match the expanded spec against the unpacked array...
+        unpacked = unpacked.each_with_index.map do |x,i|
+          # cope with '*' at end of spec
+          format = (i >= spec.length || spec[i] == ?*) ? final[0] : spec[i]
+          # if we've hit a 'V', shift it right 32 bits to get the correct value
+          x >>= 32 if format == ?V
+          x
+        end
+      end
+      unpacked
+    end
+  end
+end
+
 require File.dirname(__FILE__) + "/../config/environment"
 require 'fcgi_handler'