diff --git a/libbytesize.spec b/libbytesize.spec
index 6d97c80..fbff4d2 100644
--- a/libbytesize.spec
+++ b/libbytesize.spec
@@ -1,6 +1,6 @@
 Name:        libbytesize
 Version:     0.6
-Release:     1%{?dist}
+Release:     2%{?dist}
 Summary:     A library for working with sizes in bytes
 License:     LGPLv2+
 URL:         https://github.com/rhinstaller/libbytesize
@@ -8,6 +8,8 @@ Source0:     https://github.com/rhinstaller/libbytesize/archive/%{name}-%{versio
 
 %define realname bytesize
 
+Patch0: uli_32bit.patch
+
 BuildRequires: gmp-devel
 BuildRequires: mpfr-devel
 BuildRequires: pcre-devel
@@ -51,6 +53,7 @@ the library from Python 3 easier and more convenient.
 
 %prep
 %setup -q -n %{name}-%{version}
+%patch0 -p1
 
 %build
 %configure
@@ -87,6 +90,9 @@ find %{buildroot} -type f -name "*.la" | xargs %{__rm}
 %{python3_sitearch}/bytesize/__pycache__/*
 
 %changelog
+* Fri May  6 2016 Vratislav Podzimek <vpodzime@redhat.com> - 0.6-2
+- Beware of unsigned long int on 32bit arches (#1333149) (vpodzime)
+
 * Tue May 03 2016 Vratislav Podzimek <vpodzime@redhat.com> - 0.6-1
 - Add support for the ROUND_HALF_UP rounding mode (vpodzime)
 - Make sure we return the right radix char in human_readable() (vpodzime)
diff --git a/uli_32bit.patch b/uli_32bit.patch
new file mode 100644
index 0000000..541c98b
--- /dev/null
+++ b/uli_32bit.patch
@@ -0,0 +1,118 @@
+From d2f78ba3782534f2a2719fdbda20275f6c40c073 Mon Sep 17 00:00:00 2001
+From: Vratislav Podzimek <vpodzime@redhat.com>
+Date: Thu, 5 May 2016 15:20:43 +0200
+Subject: [PATCH] Beware of unsigned long int on 32bit arches (#1333149)
+
+GMP has no function to assign an mpz_t instance from usigned long long int and
+unsigned long int may be just a 32bit number on some architectures. So let's
+just convert the number we get into a string and use the initializer from string
+instead.
+
+Signed-off-by: Vratislav Podzimek <vpodzime@redhat.com>
+---
+ src/bs_size.c                 | 38 +++++++++++++++++++++++++++++++++++---
+ src/bs_size.h                 |  1 +
+ tests/libbytesize_unittest.py |  6 ++++++
+ 3 files changed, 42 insertions(+), 3 deletions(-)
+
+diff --git a/src/bs_size.c b/src/bs_size.c
+index 71d7b48..8c55678 100644
+--- a/src/bs_size.c
++++ b/src/bs_size.c
+@@ -3,6 +3,7 @@
+ #include <langinfo.h>
+ #include <stdarg.h>
+ #include <stdio.h>
++#include <inttypes.h>
+ #include <string.h>
+ #include <ctype.h>
+ #include <pcre.h>
+@@ -329,8 +330,16 @@ BSSize bs_size_new (void) {
+  * Returns: a new #BSSize
+  */
+ BSSize bs_size_new_from_bytes (uint64_t bytes, int sgn) {
++    char *num_str = NULL;
+     BSSize ret = bs_size_new ();
+-    mpz_set_ui (ret->bytes, bytes);
++    int ok = 0;
++
++    ok = asprintf (&num_str, "%"PRIu64, bytes);
++    if (ok == -1)
++        /* probably cannot allocate memory, there's nothing more we can do */
++        return ret;
++    mpz_set_str (ret->bytes, num_str, 10);
++    free (num_str);
+     if (sgn == -1)
+         mpz_neg (ret->bytes, ret->bytes);
+     return ret;
+@@ -475,13 +484,36 @@ BSSize bs_size_new_from_size (const BSSize size) {
+  * Returns: the @size in a number of bytes
+  */
+ uint64_t bs_size_get_bytes (const BSSize size, int *sgn, BSError **error) {
+-    if (mpz_cmp_ui (size->bytes, UINT64_MAX) > 0) {
++    char *num_str = NULL;
++    mpz_t max;
++    uint64_t ret = 0;
++    int ok = 0;
++
++    mpz_init2 (max, (mp_bitcnt_t) 64);
++    ok = asprintf (&num_str, "%"PRIu64, UINT64_MAX);
++    if (ok == -1) {
++        /* we probably cannot allocate memory so we are doomed */
++        set_error (error, BS_ERROR_FAIL, strdup("Failed to allocate memory"));
++        mpz_clear (max);
++        return 0;
++    }
++    mpz_set_str (max, num_str, 10);
++    free (num_str);
++    if (mpz_cmp (size->bytes, max) > 0) {
+         set_error (error, BS_ERROR_OVER, strdup("The size is too big, cannot be returned as a 64bit number of bytes"));
+         return 0;
+     }
++    mpz_clear (max);
+     if (sgn)
+         *sgn = mpz_sgn (size->bytes);
+-    return (uint64_t) mpz_get_ui (size->bytes);
++    if (mpz_cmp_ui (size->bytes, UINT64_MAX) <= 0)
++        return (uint64_t) mpz_get_ui (size->bytes);
++    else {
++        num_str = bs_size_get_bytes_str (size);
++        ret = strtoull (num_str, NULL, 10);
++        free (num_str);
++        return ret;
++    }
+ }
+ 
+ /**
+diff --git a/src/bs_size.h b/src/bs_size.h
+index 0a961df..e7e29c6 100644
+--- a/src/bs_size.h
++++ b/src/bs_size.h
+@@ -24,6 +24,7 @@ typedef enum {
+     BS_ERROR_INVALID_SPEC,
+     BS_ERROR_OVER,
+     BS_ERROR_ZERO_DIV,
++    BS_ERROR_FAIL
+ } BSErrorCode;
+ 
+ /**
+diff --git a/tests/libbytesize_unittest.py b/tests/libbytesize_unittest.py
+index ce4b01d..e57dc0b 100755
+--- a/tests/libbytesize_unittest.py
++++ b/tests/libbytesize_unittest.py
+@@ -123,6 +123,12 @@ class SizeTestCase(unittest.TestCase):
+         actual = SizeStruct.new_from_bytes(1024, -1).get_bytes()
+         expected = (1024, -1)
+         self.assertEqual(actual, expected)
++
++        # now let's try something bigger than MAXUINT32
++        actual = SizeStruct.new_from_bytes(5718360*1024, 1).get_bytes()
++        expected = (5718360*1024, 1)
++        self.assertEqual(actual, expected)
++
+     #enddef
+ 
+     def testNewFromSizeStruct(self):
+-- 
+2.5.5
+