kaptcha height =40

maxkey-authentications/maxkey-authentication-captcha/src/main/resources/kaptcha.properties

 kaptcha.image.width=80
-kaptcha.image.height=25
+kaptcha.image.height=40
 kaptcha.border=no
 kaptcha.obscurificator.impl=com.google.code.kaptcha.impl.ShadowGimpy
 kaptcha.textproducer.font.size=23

maxkey-authentications/maxkey-authentication-captcha/src/main/resources/kaptcha_c.properties

 kaptcha.image.width=80
-kaptcha.image.height=25
+kaptcha.image.height=40
 kaptcha.border=no
 #kaptcha.obscurificator.impl=com.google.code.kaptcha.impl.ShadowGimpy
 kaptcha.obscurificator.impl=com.google.code.kaptcha.impl.Ripple