gradle.properties special characters in proxy password

Question

I just can't get to work gradle with my corporate proxy. I got it to work though with node.js in the .npmrc file.

My password has a "<" character in the password. In the .npmrc file I had to escape it by writing "%3C" instead:

proxy=http://na_me:123%[email protected]:80/
https-proxy=http://na_me:123%[email protected]:80/

My gradle.properties look like this:

systemProp.http.proxyHost=proxy.net
systemProp.http.proxyPort=80
systemProp.http.proxyUser=na_me
systemProp.http.proxyPassword=123<456
systemProp.http.nonProxyHosts=localhost

systemProp.https.proxyHost=proxy.net
systemProp.https.proxyPort=80
systemProp.https.proxyUser=na_me
systemProp.https.proxyPassword=123<456
systemProp.https.nonProxyHosts=localhost

Is that syntax correct in theory? Or do I have to escape anything like the "<"?

I always get the error:

Error: Unable to tunnel through proxy. 
Proxy returns "HTTP/1.1 407 Proxy Authentication Required"

I tried using the global gradle.properties file in my user folder and also creating the file in C:\Program Files\Android\Android Studio\gradle.