IDEA tests fail on big endian architectures like ppc or s390, on both 32 and 64 bit.

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make[2]: Entering directory `/builddir/build/BUILD/gnupg-1.4.13/checks'
gpg (GnuPG) 1.4.13
Copyright (C) 2012 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later http://gnu.org/licenses/gpl.html
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Home: .
Supported algorithms:
Pubkey: RSA, RSA-E, RSA-S, ELG-E, DSA
Cipher: IDEA, 3DES, CAST5, BLOWFISH, AES, AES192, AES256, TWOFISH,

CAMELLIA128, CAMELLIA192, CAMELLIA256

Hash: MD5, SHA1, RIPEMD160, SHA256, SHA384, SHA512, SHA224
Compression: Uncompressed, ZIP, ZLIB, BZIP2
PASS: version.test
PASS: mds.test
PASS: decrypt.test
PASS: decrypt-dsa.test
MD5 SHA1 RIPEMD160 SHA256 SHA384 SHA512 SHA224 | PASS: sigs.test
PASS: sigs-dsa.test
IDEA FAIL: encrypt.test
IDEA FAIL: encrypt-dsa.test
PASS: seat.test
PASS: clearsig.test
PASS: encryptp.test
PASS: detach.test
PASS: armsigs.test
PASS: armencrypt.test
PASS: armencryptp.test
PASS: signencrypt.test
PASS: signencrypt-dsa.test
PASS: armsignencrypt.test
PASS: armdetach.test
PASS: armdetachm.test
PASS: detachm.test
PASS: genkey1024.test
IDEA FAIL: conventional.test
IDEA FAIL: conventional-mdc.test
PASS: multisig.test
PASS: verify.test

PASS: armor.test

4 of 27 tests failed

Please report to http://bugs.gnupg.org

Please let me know if you need more details or anything else.