> =?ISO-2022-JP?B?ABde4tUmglUjllj87KjkjfdHJKK54dJF==
>  =?ISO-2022-JP?B?klFGGkuJYcfg75kKOLKLlmHKHkgh4443==

$ echo klFGGkuJYcfg75kKOLKLlmHKHkgh4443==|mimencode -u|nkf
Warning: base64 decoder saw premature EOF!
嘆FK餌ヌ瑜8イ許aハH!緕7

参考：2003/08/03(日)04時20分00秒