[Nexus One Q&A, Help & Troubleshooting] dmanbuhnik:
I have the same issue

I have tomato router, all ports (1-65535) are open, the ip for the android device is in DMZ (for checking)

my android is n1 with cm6.0.0 (but the problem is much older)

as I can see it, all https connects get 'timeout'

while I'm on wifi I will get errors like those (from logcat):

E/CheckinTask( 247): Checkin failed: [URL]https://android.clients.google.com/checkin[/URL] (request #0)
E/CheckinTask( 247): java.net.SocketTimeoutException: Read timed out
E/CheckinTask( 247): at org.apache.harmony.xnet.provider.jsse.OpenSSLSocketImpl.nativeread(Native Method)
E/CheckinTask( 247): at org.apache.harmony.xnet.provider.jsse.OpenSSLSocketImpl.access$300(OpenSSLSocketImpl.java:55)

E/CheckinTask( 247): at org.apache.harmony.xnet.provider.jsse.OpenSSLSocketImpl$SSLInputStream.read(OpenSSLSocketImpl
.java:542)
E/CheckinTask( 247): at org.apache.http.impl.io.AbstractSessionInputBuffer.fillBuffer(AbstractSessionInputBuffer.java
:103)
E/CheckinTask( 247): at org.apache.http.impl.io.AbstractSessionInputBuffer.readLine(AbstractSessionInputBuffer.java:1
91)
E/CheckinTask( 247): at org.apache.http.impl.conn.DefaultResponseParser.parseHead(DefaultResponseParser.java:82)
E/CheckinTask( 247): at org.apache.http.impl.io.AbstractMessageParser.parse(AbstractMessageParser.java:174)
E/CheckinTask( 247): at org.apache.http.impl.AbstractHttpClientConnection.receiveResponseHeader(AbstractHttpClientCon
nection.java:179)
E/CheckinTask( 247): at org.apache.http.impl.conn.DefaultClientConnection.receiveResponseHeader(DefaultClientConnecti
on.java:235)
E/CheckinTask( 247): at org.apache.http.impl.conn.AbstractClientConnAdapter.receiveResponseHeader(AbstractClientConnA
dapter.java:259)
E/CheckinTask( 247): at org.apache.http.protocol.HttpRequestExecutor.doReceiveResponse(HttpRequestExecutor.java:279)
E/CheckinTask( 247): at org.apache.http.protocol.HttpRequestExecutor.execute(HttpRequestExecutor.java:121)
E/CheckinTask( 247): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:410)
E/CheckinTask( 247): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
E/CheckinTask( 247): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
E/CheckinTask( 247): at android.net.http.AndroidHttpClient.execute(AndroidHttpClient.java:248)
E/CheckinTask( 247): at com.google.android.common.http.GoogleHttpClient.executeWithoutRewriting(GoogleHttpClient.java
:203)
E/CheckinTask( 247): at com.google.android.common.http.GoogleHttpClient.execute(GoogleHttpClient.java:245)
E/CheckinTask( 247): at com.google.android.common.http.GoogleHttpClient.execute(GoogleHttpClient.java:313)
E/CheckinTask( 247): at com.google.android.gsf.checkin.CheckinTask.sendRequest(CheckinTask.java:239)
E/CheckinTask( 247): at com.google.android.gsf.checkin.CheckinTask.doInBackground(CheckinTask.java:146)
E/CheckinTask( 247): at com.google.android.gsf.checkin.CheckinService$1.doInBackground(CheckinService.java:221)
E/CheckinTask( 247): at com.google.android.gsf.checkin.CheckinService$1.doInBackground(CheckinService.java:228)
E/CheckinTask( 247): at android.os.AsyncTask$2.call(AsyncTask.java:185)
E/CheckinTask( 247): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
E/CheckinTask( 247): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
E/CheckinTask( 247): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1068)
E/CheckinTask( 247): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:561)
E/CheckinTask( 247): at java.lang.Thread.run(Thread.java:1096)

which is another symptom of the problem

for testing purposes I downloaded Dolphin HD browser (which I think uses the same engine like the default android browser) and everything works great, wifi or 3g.

the best test case is to try and login to any google service, on wifi with android browser - timeout, on 3g/other browser - working great