Please first read Comments section here and in 6317399.

In sun/tools/javazic/Gen.java (5.0u4):

// wrong line 223
	    byte[] b = Main.getVersionName().getBytes();
// correction
	    byte[] b = Main.getVersionName().getBytes("US-ASCII");
// wrong line 240
		    raf.write(key.getBytes(), 0, size);
// correction
		    raf.write(key.getBytes("US-ASCII"), 0, size);
// wrong lines 296-298
		raf.write(key.getBytes(), 0, key_size);
		raf.writeByte(alias_size & 0xFF);
		raf.write(alias.getBytes(), 0, alias_size);
// correction
		raf.write(key.getBytes("US-ASCII"), 0, key_size);
		raf.writeByte(alias_size & 0xFF);
		raf.write(alias.getBytes("US-ASCII"), 0, alias_size);