diff --git a/shared/Base/Utility.cpp b/shared/Base/Utility.cpp
index 9132efe1..0acb5616 100644
--- a/shared/Base/Utility.cpp
+++ b/shared/Base/Utility.cpp
@@ -807,45 +807,45 @@ Object MakeULongObj(HSQUIRRELVM vm, Uint64 val)
 }
 
 // ------------------------------------------------------------------------------------------------
-Int64 FetchSLongObjVal(Object & val)
+Int64 FetchSLongObjVal(const Object & val)
 {
     // Obtain the initial stack size
     const StackGuard sg(DefaultVM::Get());
     // Push the specified object onto the stack
-    Var< Object & >::push(DefaultVM::Get(), val);
+    Var< const Object & >::push(DefaultVM::Get(), val);
     // Retrieve and return the object value from the stack
     return PopStackSLong(DefaultVM::Get(), -1);
 }
 
 // ------------------------------------------------------------------------------------------------
-Uint64 FetchULongObjVal(Object & val)
+Uint64 FetchULongObjVal(const Object & val)
 {
     // Obtain the initial stack size
     const StackGuard sg(DefaultVM::Get());
     // Push the specified object onto the stack
-    Var< Object & >::push(DefaultVM::Get(), val);
+    Var< const Object & >::push(DefaultVM::Get(), val);
     // Retrieve and return the object value from the stack
     return PopStackSLong(DefaultVM::Get(), -1);
 }
 
 // ------------------------------------------------------------------------------------------------
-Int64 FetchSLongObjVal(HSQUIRRELVM vm, Object & val)
+Int64 FetchSLongObjVal(HSQUIRRELVM vm, const Object & val)
 {
     // Obtain the initial stack size
     const StackGuard sg(vm);
     // Push the specified object onto the stack
-    Var< Object & >::push(vm, val);
+    Var< const Object & >::push(vm, val);
     // Retrieve and return the object value from the stack
     return PopStackSLong(vm, -1);
 }
 
 // ------------------------------------------------------------------------------------------------
-Uint64 FetchULongObjVal(HSQUIRRELVM vm, Object & val)
+Uint64 FetchULongObjVal(HSQUIRRELVM vm, const Object & val)
 {
     // Obtain the initial stack size
     const StackGuard sg(vm);
     // Push the specified object onto the stack
-    Var< Object & >::push(vm, val);
+    Var< const Object & >::push(vm, val);
     // Retrieve and return the object value from the stack
     return PopStackSLong(vm, -1);
 }
diff --git a/shared/Base/Utility.hpp b/shared/Base/Utility.hpp
index cad273a3..4ea71c4a 100644
--- a/shared/Base/Utility.hpp
+++ b/shared/Base/Utility.hpp
@@ -1468,22 +1468,22 @@ Object MakeULongObj(HSQUIRRELVM vm, Uint64 val);
 /* ------------------------------------------------------------------------------------------------
  * Retrieve a signed 64 bit integer from an signed long integer object.
 */
-Int64 FetchSLongObjVal(Object & val);
+Int64 FetchSLongObjVal(const Object & val);
 
 /* ------------------------------------------------------------------------------------------------
  * Retrieve a unsigned 64 bit integer from an unsigned long integer object.
 */
-Uint64 FetchULongObjVal(Object & val);
+Uint64 FetchULongObjVal(const Object & val);
 
 /* ------------------------------------------------------------------------------------------------
  * Retrieve a signed 64 bit integer from an signed long integer object.
 */
-Int64 FetchSLongObjVal(HSQUIRRELVM vm, Object & val);
+Int64 FetchSLongObjVal(HSQUIRRELVM vm, const Object & val);
 
 /* ------------------------------------------------------------------------------------------------
  * Retrieve a unsigned 64 bit integer from an unsigned long integer object.
 */
-Uint64 FetchULongObjVal(HSQUIRRELVM vm, Object & val);
+Uint64 FetchULongObjVal(HSQUIRRELVM vm, const Object & val);
 
 /* ------------------------------------------------------------------------------------------------
  * Attempt to pop the value at the specified index on the stack as a native integer.