I try to install [Walkaround](http://code.google.com/p/walkaround/), a project based on Google Wave. I followed [the official wiki](http://code.google.com/p/walkaround/wiki/RunningTheCode) for installation.

But during the last step (./runant run), I've 100 errors:

```
Proto.java:7: package com.google.protobuf does not exist
      com.google.protobuf.ExtensionRegistry registry) {
                         ^
Proto.java:12450: package com.google.protobuf.Descriptors does not exist
  private static com.google.protobuf.Descriptors.Descriptor
                                                ^
Proto.java:12453: package com.google.protobuf.GeneratedMessage does not exist
    com.google.protobuf.GeneratedMessage.FieldAccessorTable

...
...
100 errors

```

**Similar topic:** [Problems using protobufs with java and scala](https://stackoverflow.com/questions/8265801/problems-using-protobufs-with-java-and-scala). So I try this solution after searching a proto.jar and the Proto.java:

```
javac -cp 
    ~/walkaround/third_party_src/wave/trunk/dist/proto.jar
    ~/walkaround/proto_src/com/google/walkaround/proto/Proto.java

```

**But I get the same 100 errors.**

Someone can help me? I have no knowledge about Ubuntu Linux and Java environment.