Confirmed, updating to 15.05 fixed the switch history feature for us.

http://galaxy.readthedocs.org/en/master/releases/15.05_announce.html

Now running:

$ hg branch
release_15.05
$ hg log | head
changeset:   17125:e837a68e8d14
tag:         tip
parent:      17121:7a4e3a661a76
parent:      17124:46a4ef8850b5
user:        Nate Coraor <nate@bx.psu.edu>
date:        Fri May 15 15:21:34 2015 -0400
summary:     Merge stable to default

Thanks Dannon,

Peter

On Fri, Jul 24, 2015 at 10:41 AM, Peter Cock <p.j.a.cock@googlemail.com> wrote:
> I think we were running 15.03.1,
>
> $ hg branch
> stable
> $ hg log | head
> changeset:   17050:6395e7035143
> tag:         tip
> parent:      17049:708cab19708d
> parent:      17048:28113eeee212
> user:        Nate Coraor <nate@bx.psu.edu>
> date:        Mon Mar 16 22:50:21 2015 -0400
> summary:     Merge v15.03.1 to default
>
> It sounds like updating to 15.05 should fix this then...
>
> Peter
>
> On Thu, Jul 23, 2015 at 8:57 PM, Ping Luo <luop0812@gmail.com> wrote:
>> Dannon,
>>
>> The release I am using is v15.03.
>>
>> Ping
>>
>> On Thu, Jul 23, 2015 at 10:15 AM, Dannon Baker <dannon.baker@gmail.com>
>> wrote:
>>>
>>> What revision are you running?  I'm seeing my proxy-prefix get appended
>>> correctly in both release_15.05 and in current -dev.
>>>
>>> On Thu, Jul 23, 2015 at 5:10 AM Peter Cock <p.j.a.cock@googlemail.com>
>>> wrote:
>>>>
>>>> Hello Ping,
>>>>
>>>> I can confirm this bug.
>>>>
>>>> I noticed this some time back when the new history was in beta,
>>>> but neglected to explore what was wrong. Apologies.
>>>>
>>>> When looking at:
>>>>
>>>> http://our_server_name/galaxy/history/view_multiple
>>>>
>>>> Via Firefox I can see the "switch" button is triggering a URL like:
>>>>
>>>> http://our_server_name/history/set_as_current?id=cde77e676c9d11d1
>>>>
>>>> The Apache access log contains lines like this:
>>>>
>>>> "GET /history/set_as_current?id=cde77e676c9d11d1 HTTP/1.1" 404 294
>>>> "http://our_server_name/galaxy/history/view_multiple" "Mozilla/5.0
>>>> (Macintosh; Intel Mac OS X 10.10; rv:39.0) Gecko/20100101
>>>> Firefox/39.0"
>>>>
>>>> The Apache error log contains lines like this:
>>>>
>>>> File does not exist: /var/www/html/history, referer:
>>>> http://our_server_name/galaxy/history/view_multiple
>>>>
>>>> We're using "galaxy" as a prefix for this instance using this in the
>>>> config:
>>>>
>>>> [app:main]
>>>> filter-with = proxy-prefix
>>>> cookie_path = /galaxy
>>>>
>>>> Regards,
>>>>
>>>> Peter
>>>>
>>>> On Wed, Jul 22, 2015 at 8:26 PM, Ping Luo <luop0812@gmail.com> wrote:
>>>> > Hello,
>>>> >
>>>> > Our galaxy server is served under a sub-directory "/myserver". So far
>>>> > everything works except the "Switch to" button in "view all history".
>>>> > When
>>>> > clicking it, there is no response. From apache server access log, I see
>>>> > this
>>>> > message
>>>> >
>>>> >     "GET /history/set_as_current?id=9a8f74b3b768f8f1 HTTP/1.1" 404 304
>>>> >
>>>> > And in the apache error log, I see
>>>> >
>>>> >      File does not exist: /www/htdocs/history, referer:
>>>> > https://xxx.xxx.xxx/myserver/history/view_multiple
>>>> >
>>>> > Since the prefix "/myserver" is not properly prepended in the equest,
>>>> > the
>>>> > request is not properly routed. It tries to retrive the history page
>>>> > from
>>>> > the document root /www/htdocs.
>>>> >
>>>> > So far, all other requests seems have a proper prefix, for example
>>>> >
>>>> > "GET /myserver/history/current_history_json HTTP/1.1" 200 1430
>>>> > "GET /myserver/api/histories/7a11fc800eeb71e9/contents HTTP/1.1" 200
>>>> > 15876
>>>> > "GET /myserver/history/view_multiple HTTP/1.1" 200 27296
>>>> > "GET /myserver/static/style/base.css?v=1437576796 HTTP/1.1" 304 -
>>>> >
>>>> >
>>>> > Please help to resolve the issue.
>>>> >
>>>> > Thanks,
>>>> >
>>>> > Ping
>>>> >
>>>> >