I have done exactly what you said for the update from 1.3 to 1.4.0 and i have got this error message.
It is really incridible that such things may happend.
Here is the message :
Fatal: Call to undefined method Premium_ImportCommon::acl_check() in /home/pixemcom/public_html/epesi/modules/Premium/Import/ImportCommon_0.php on line 15
This message is repeated 6 times.
This happens after i put the password
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