Mail step with attachment name with "%" generates java exception

We need to process emails and their attachments. We have not control of what the attachment are been named, we found that if the mail attachment name has "%" on it then an java exception get generated. In this case we create and email and we attached a file name 46575400%.what.pdf as an example

2018/05/18 17:56:15 - GeteMails - ERROR (version 8.0.0.0-28, build 8.0.0.0-28 from 2017-11-05 07.27.50 by buildguy) : Unexpected error:
2018/05/18 17:56:15 - GeteMails - org.pentaho.di.core.exception.KettleException:
2018/05/18 17:56:15 - GeteMails - Error saving attached files of message number 3 in folder [c:\processing\Deleteme]!
2018/05/18 17:56:15 - GeteMails -
2018/05/18 17:56:15 - GeteMails - org.pentaho.di.core.exception.KettleException:
2018/05/18 17:56:15 - GeteMails - org.pentaho.di.core.exception.KettleException:
2018/05/18 17:56:15 - GeteMails - org.pentaho.di.core.exception.KettleFileException:
2018/05/18 17:56:15 - GeteMails -
2018/05/18 17:56:15 - GeteMails - Unable to get VFS File object for filename 'c:\processing\Deleteme/46575400%what.pdf' : Invalid URI escape sequence "%wh".
2018/05/18 17:56:15 - GeteMails - Invalid URI escape sequence "%wh".

Does anybody has any idea for a workaround?

regards