Proguard issue with xpath

[EnricoAncis]

have a issue with an Android app: when I compile with minifyEnabled true
I guess it's an issue with the obfuscation, I have this error:

 b.b.a.c.a: The xpath expression //LoginServicesResponse specified for e was an invalid XPath expression 
...
...
Caused by: java.lang.ClassNotFoundException: Didn't find class "org.jaxen.saxpath.base.XPathReader" on path: DexPathList[[zip file "/data/app/xxx.xxxx.xxxx-VosorY5JNoJmDt20C6tGgg==/base.apk"],nativeLibraryDirectories=[/data/app/re.touchwa.braccointernational-VosorY5JNoJmDt20C6tGgg==/lib/arm64, /system/lib64, /system/product/lib64]]

My class with //LoginServicesResponse start with:

@XMLObject("//LoginServicesResponse")
public class LoginServicesResponse {
    @XMLField("LoginServicesResult")
    private String result;
   ...

I'd add the right rule on Proguard file, I've tried with:

I'd add the right rule on Proguard file, I've tried with:

-keepnames class org.jaxen.saxpath.base.XPathReader
or

-keep class org.jaxen.saxpath.base.XPathReader
or

-keep classorg.jaxen.saxpath.base.XPathReader.** { *; }
but they don't solve the problem.

What am I doing wrong?

[AlexGilleran]

No idea - maybe try keeping the entire jaxen library?

[EnricoAncis]

Even the same issue

-keep class org.jaxen.** { *; }