diff --git a/build/pkgs/pycrypto/SPKG.txt b/build/pkgs/pycrypto/SPKG.txt
index d6a259770bd..345382f9ac9 100644
--- a/build/pkgs/pycrypto/SPKG.txt
+++ b/build/pkgs/pycrypto/SPKG.txt
@@ -27,10 +27,15 @@ Python 2.2 license.
 
 == Special Update/Build Instructions ==
 
- * None
+=== Patches ===
+
+ * freebsd.patch: let pycrypto build on FreeBSD.
 
 == Changelog ==
 
+=== pycrypto-2.1.0.p0 (Jean-Pierre Flori, 4 July 2013) ===
+ * #12399: Let pycrypto build on FreeBSD.
+
 === pycrypto-2.1.0 (Minh Van Nguyen, June 26th, 2010) ===
 
  * Ticket #9338; upgrade to PyCrypto 2.1.0.
diff --git a/build/pkgs/pycrypto/package-version.txt b/build/pkgs/pycrypto/package-version.txt
index 7ec1d6db408..7e41e597591 100644
--- a/build/pkgs/pycrypto/package-version.txt
+++ b/build/pkgs/pycrypto/package-version.txt
@@ -1 +1 @@
-2.1.0
+2.1.0.p0
diff --git a/build/pkgs/pycrypto/patches/freebsd.patch b/build/pkgs/pycrypto/patches/freebsd.patch
new file mode 100644
index 00000000000..267b0505394
--- /dev/null
+++ b/build/pkgs/pycrypto/patches/freebsd.patch
@@ -0,0 +1,13 @@
+--- src/src/libtom/tomcrypt_pk.h-orig	2012-01-21 
+19:43:56.000000000 +0000
++++ src/src/libtom/tomcrypt_pk.h	2012-01-21 
+19:45:01.000000000 +0000
+@@ -496,7 +496,7 @@
+ int der_printable_value_decode(int v);
+ 
+ /* UTF-8 */
+-#if (defined(SIZE_MAX) || __STDC_VERSION__ >= 199901L || defined(WCHAR_MAX) || defined(_WCHAR_T) || defined(_WCHAR_T_DEFINED)) && !defined(LTC_NO_WCHAR)
++#if (defined(SIZE_MAX) || __STDC_VERSION__ >= 199901L || defined(WCHAR_MAX) || defined(_WCHAR_T) || defined(_WCHAR_T_DEFINED) || defined(_GCC_WCHAR_T)) && !defined(LTC_NO_WCHAR)
+ #include <wchar.h>
+ #else
+ typedef ulong32 wchar_t;
diff --git a/build/pkgs/pycrypto/spkg-check b/build/pkgs/pycrypto/spkg-check
index 878f884c9af..7f25a7d9040 100755
--- a/build/pkgs/pycrypto/spkg-check
+++ b/build/pkgs/pycrypto/spkg-check
@@ -1,41 +1,16 @@
 #!/usr/bin/env bash
 
-if [ -z $SAGE_LOCAL ]; then
-    echo "SAGE_LOCAL undefined... exiting"
-    echo "Maybe run 'sage -sh'?"
+if [ -z "$SAGE_LOCAL" ]; then
+    echo >&2 "SAGE_LOCAL undefined ... exiting"
+    echo >&2 "Maybe run 'sage --sh'?"
     exit 1
 fi
 
-# Let the user set an environment variable CFLAG64 to indicate the flag
-# for the C compiler to build 64-bit code. If not set, assume it is -m64
-# as that is what is used by both GCC and SunStudio, but -m64 is not used
-# by IBM's compiler on AIX or HP's compiler on HP-UX.
-
-if [ -z $CFLAG64 ]; then
-    # -m64 is used by gcc and SunStudio
-    CFLAG64=-m64
-fi
-
-# Likewise to build C++ code.
-if [ -z $CXXFLAG64 ]; then
-    # -m64 is used by gcc and SunStudio
-    CXXFLAG64=-m64
-fi
-
-if [ "x$SAGE64" = xyes ]; then
-    CFLAGS="$CFLAGS $CFLAG64" && export CFLAGS
-    CXXFLAGS="$CXXFLAGS $CXXFLAG64" && export CXXFLAGS
-    LDFLAGS="$LDFLAGS $CFLAG64" && export LDFLAGS
-    # Very rare is CPPFLAGS needed, but sometimes it is.
-    CPPFLAGS="$CPPFLAGS $CFLAG64" && export CPPFLAGS
-fi
-
 cd src
 
 echo "PyCrypto will now be tested"
 python setup.py test
-
 if [ $? -ne 0 ]; then
-    echo "An error occurred while testing PyCrypto... exiting"
+    echo >&2 "Error: PyCrypto failed to pass its test suite."
     exit 1
 fi
diff --git a/build/pkgs/pycrypto/spkg-install b/build/pkgs/pycrypto/spkg-install
index fec56ba41b4..1af6e790d6d 100755
--- a/build/pkgs/pycrypto/spkg-install
+++ b/build/pkgs/pycrypto/spkg-install
@@ -1,24 +1,41 @@
 #!/usr/bin/env bash
 
-if [ "$SAGE_LOCAL" = "" ]; then
-    echo "SAGE_LOCAL undefined... exiting"
-    echo "Maybe run 'sage -sh'?"
+if [ -z "$SAGE_LOCAL" ]; then
+    echo >&2 "SAGE_LOCAL undefined ... exiting"
+    echo >&2 "Maybe run 'sage --sh'?"
     exit 1
 fi
 
-if [ "x$SAGE64" = xyes ]; then
-    echo "64-bit build"
-    CFLAGS="-O2 -g -m64 "; export CFLAGS
-    LDFLAGS="-m64 "; export LDFLAGS
+cd src
+
+# Apply patches.  See SPKG.txt for information about what each patch
+# does.
+for patch in ../patches/*.patch; do
+    [ -r "$patch" ] || continue  # Skip non-existing or non-readable patches
+    patch -p1 <"$patch"
+    if [ $? -ne 0 ]; then
+        echo >&2 "Error applying '$patch'"
+        exit 1
+    fi
+done
+
+if [ "$SAGE_DEBUG" = "yes" ]; then
+    echo "Building a debug version of PyCrypto."
+    export CFLAGS="-O0 -g $CFLAGS"
+else
+    export CFLAGS="-O2 -g $CFLAGS"
 fi
 
-CFLAGS="-I$SAGE_LOCAL/include -L$SAGE_LOCAL/lib $CFLAGS"
-export CFLAGS
+if [ "$SAGE64" = "yes" ]; then
+    echo "Building a 64-bit version of PyCrypto."
+    export ABI=64
+    CFLAGS="-m64 $CFLAGS"
+fi
 
-cd src
+CFLAGS="-I$SAGE_LOCAL/include -L$SAGE_LOCAL/lib $CFLAGS"
 
 python setup.py install
 if [ $? -ne 0 ]; then
-    echo "Error installing PyCrypto... exiting"
+    echo >&2 "Error: Failed to install PyCrypto."
     exit 1
 fi