diff --git a/gramps/gen/plug/docgen/graphdoc.py b/gramps/gen/plug/docgen/graphdoc.py
index 06ae900c8..bca8cbfed 100644
--- a/gramps/gen/plug/docgen/graphdoc.py
+++ b/gramps/gen/plug/docgen/graphdoc.py
@@ -598,7 +598,10 @@ class GVDotDoc(GVDocBase):
         if self._filename[-3:] != ".gv":
             self._filename += ".gv"
 
-        dotfile = open(self._filename, "w")
+        if sys.version_info[0] < 3:
+            dotfile = open(self._filename, "w")
+        else:
+            dotfile = open(self._filename, "wb")
         dotfile.write(self._dot.getvalue())
         dotfile.close()
 
diff --git a/gramps/plugins/graph/gvrelgraph.py b/gramps/plugins/graph/gvrelgraph.py
index 259c79261..9958ca76e 100644
--- a/gramps/plugins/graph/gvrelgraph.py
+++ b/gramps/plugins/graph/gvrelgraph.py
@@ -47,6 +47,7 @@ from functools import partial
 # GRAMPS modules
 #
 #------------------------------------------------------------------------
+from gramps.gen.constfunc import conv_to_unicode
 from gramps.gen.plug.menu import (BooleanOption, EnumeratedListOption, FilterOption,
                           PersonOption, ColorOption)
 from gramps.gen.plug.report import Report
@@ -172,7 +173,8 @@ class RelGraphReport(Report):
         children
         """
         # Hash people in a dictionary for faster inclusion checking
-        person_dict = dict([handle, 1] for handle in self.person_handles)
+        person_dict = dict([conv_to_unicode(handle, 'utf-8'), 1]
+                                for handle in self.person_handles)
             
         for person_handle in self.person_handles:
             person = self.database.get_person_from_handle(person_handle)
@@ -182,7 +184,7 @@ class RelGraphReport(Report):
                 father_handle = family.get_father_handle()
                 mother_handle = family.get_mother_handle()
                 for child_ref in family.get_child_ref_list():
-                    if child_ref.ref == person_handle:
+                    if child_ref.ref == conv_to_unicode(person_handle, 'utf-8'):
                         frel = child_ref.frel
                         mrel = child_ref.mrel
                         break
@@ -241,7 +243,7 @@ class RelGraphReport(Report):
             (shape, style, color, fill) = self.get_gender_style(person)
             url = ""
             if self.includeurl:
-                h = person_handle
+                h = conv_to_unicode(person_handle, 'utf-8')
                 dirpath = "ppl/%s/%s" % (h[-1], h[-2])
                 dirpath = dirpath.lower()
                 url = "%s/%s.html" % (dirpath, h)