When using the --sign option for androiddeployqt to sign apk with a keystore key alias name "keystore" it fails with error "Option lacks argument".

--sign android.keystore keystore --storepass xxxx --keypass xxxx 

qml: Signing Android package. 
Option lacks argument 
Please type jarsigner -help for usage 
qml: jarsigner command failed. 

Signing works when using the alias name as "keystore1" instead of "keystore". Also the issue doesn't reproduce on OS X host.
Using the jarsigner directly works with "keystore" file name.