Xml SSOAP在发出请求时给出错误

我正在尝试连接到我当地的政府统计网络服务，但不断出现错误

# install.packages("SSOAP", repos = "http://www.omegahat.org/R", dependencies = TRUE, type = "source")
library(SSOAP)
library(XML)

wsdl <- "http://analitica.spb.ru/UniversalWSAnalitica-war/UniversalWSAnaliticaService?wsdl"
doc <- xmlInternalTreeParse(wsdl)

def <- processWSDL(doc)
iac_iface <- genSOAPClientInterface(def = def)

我试过Python库泡沫，效果也很好。有人能告诉我SSOAP的使用有什么问题吗？ R版本3.1.2，基于32位Debian测试

library(httr)
xml.request  <- 
"<soapenv:Envelope xmlns:soapenv=\"http://schemas.xmlsoap.org/soap/envelope/\" xmlns:ws=\"http://ws.universal.department14.iac.spb.ru/\">
   <soapenv:Header/>
   <soapenv:Body>
      <ws:getIndTree>
         <dateActual>24.06.2013 11:00:00</dateActual>
         <treeLVL>1</treeLVL>
      </ws:getIndTree>
   </soapenv:Body>
</soapenv:Envelope>"
r <- POST("http://analitica.spb.ru/UniversalWSAnalitica-war/UniversalWSAnaliticaService", body = xml.request)
stop_for_status(r)
content(r)