diff --git a/src/cpyrt/Converters.cxx b/src/cpyrt/Converters.cxx
index c647696..4771e80 100644
--- a/src/cpyrt/Converters.cxx
+++ b/src/cpyrt/Converters.cxx
@@ -4271,11 +4271,13 @@ static struct InitConvFactories_t {
     gf["const std::wstring &"] = gf["std::wstring"];
     gf["const " WSTRING1 " &"] = gf["std::wstring"];
     gf["const " WSTRING2 " &"] = gf["std::wstring"];
-    // VoidPtrRefConverter should only be used for const references to pointers
-    gf["const void*&"] = (cf_t) + [](cdims_t) {
+    // void*& is exempt from the T*& ban: the callee updates the proxy's
+    // held pointer through the opaque handle
+    gf["void*&"] = (cf_t) + [](cdims_t) {
       static VoidPtrRefConverter c{};
       return &c;
     };
+    gf["const void*&"] = gf["void*&"];
     gf["void**"] =
         (cf_t) + [](cdims_t d) { return new VoidPtrPtrConverter{d}; };
     gf["void ptr"] = gf["void**"];
diff --git a/test/test_conversions.py b/test/test_conversions.py
index 8741534..65b1600 100644
--- a/test/test_conversions.py
+++ b/test/test_conversions.py
@@ -138,3 +138,19 @@ def test05_bool_conversions(self):
         assert ns.Test1()
         assert ns.Test2(True)
         assert not ns.Test2(False)
+
+    def test07_mutable_voidp_reference(self):
+        """An object can be passed through a non-const void*& argument"""
+
+        import cppjit
+
+        cppjit.cppdef("""\
+        namespace VoidPtrRef {
+            struct Obj { int v = 5; };
+            bool is_same(void*& p, Obj* o) { return p == (void*)o; }
+        }""")
+
+        ns = cppjit.gbl.VoidPtrRef
+        o = ns.Obj()
+
+        assert ns.is_same(o, o)