WAS SISERA SLEEPING, OR STANDING, WHEN JAEL KILLED HIM?

Judges 4:21  Then Jael Heber's wife took a nail of the tent, and took an hammer in her hand, and went softly unto him, and smote the nail into his temples, and fastened it into the ground: for he was fast asleep and weary. So he died. (KJV) Judges 5:26-27  She put her hand to the nail, and her right hand to the workmen's hammer; and with the hammer she smote Sisera, she smote off his head, when she had pierced and stricken through his temples.  At her feet he bowed, he fell, he lay down: at her feet he bowed, he fell: where he bowed, there he fell down dead. (KJV)

Judges 5 does not say that Sisera was standing when Jael drove the nail into his head.  Most likely, he woke up when she drove the nail in, stood up, and then collapsed as described in Judges 5.  In fact, it would have been very difficult to stab him with the nail in the temples had he not been asleep.  After he had finally died, she fastened the nail to the ground as described in Judges 4.  Not a contradiction.